Exhibit 10.28

PROMISSORY NOTE

(Amortizing Term Loan)

October 7, 2011

For value received, Borrower promises to pay to the order of Lender at Zions First National Bank, Corporate Banking Group, One South Main Street, Suite 200, Salt Lake City, Utah 84111, or at such other address as the holder of this Promissory Note at any given time may designate by written notice to Borrower, the sum of $2,500,000.00, in lawful money of the United States with interest thereon calculated and payable as provided herein.

Definitions

Terms used in the singular shall have the same meaning when used in the plural and vice versa. Capitalized term used but not defined herein shall have the meanings given to such terms in the Loan Agreement (as defined herein). As used in this Promissory Note, the term:

“Applicable Margin” means 4.50% per annum.

“Default Rate” means the interest rate in effect hereunder from time to time (including any applicable margin) plus 3.0% per annum.

“Dollars” and the sign “$” mean lawful money of the United States.

“FHLB Rate” means the rate per annum quoted by Lender as Lender’s FHLB rate based upon the FHLB Seattle rate as quoted in Bloomberg, or on the FHLB Seattle internet web site at www.FHLBsea.com, or other comparable service selected by Lender for the applicable Interest Period. This definition of FHLB Rate is to be strictly interpreted and is not intended to serve any purpose other than providing an index to determine the rate used herein. It is not necessarily the lowest rate charged by Lender on its loans. If the FHLB Rate becomes unavailable during the term of this Promissory Note, Lender may designate a substitute index after notifying Borrower.

“Interest Period” means, with respect to any advance or balance for which interest is based on the LIBOR Rate, the period commencing on the date such advance is made or, as to an existing balance, the date selected by Borrower and ending, as Borrower may select, on the numerically corresponding day in the third calendar month or first, second or third year thereafter, except that each such Interest Period that commences on the last Banking Business Day of a calendar month (or on any day for which there is no numerically corresponding day in

the appropriate subsequent calendar month) shall end on the last Banking Business Day of the appropriate subsequent calendar month; provided that all of the foregoing provisions relating to Interest Periods are subject to the following:

“LIBOR Rate” applicable to any Interest Period means the rate per annum quoted by Lender two (2) Banking Business Days prior to the commencement of the Interest Period as its LIBOR Rate based upon quotes from the London Interbank Offered Rate from the British Bankers Association Interest Settlement Rates as quoted for United States Dollars by Bloomberg or other comparable services selected by Lender for the applicable Interest Period. This definition of LIBOR Rate is to be strictly interpreted and is not intended to serve any purpose other than providing an index to determine the interest rate used herein. The LIBOR Rate of Lender may not necessarily be the same as the quoted offered side in the Eurodollar time deposit market quoted by any particular institution or service applicable to any Interest Period. It is not the lowest rate at which Lender may make loans to any of its customers, either now or in the future.

“Loan Agreement” means the Loan Agreement of even date herewith between Lender and Borrower, together with any exhibits, schedules, amendments, addenda, and modifications thereto.

“Maturity Date” shall have the meaning set forth in the heading of this Promissory Note.

“Ninety Day FHLB Rate” means the rate per annum quoted by Lender as Lender’s Ninety Day FHLB rate based upon the FHLB Seattle rate as quoted in Bloomberg, or on the FHLB Seattle internet web site at www.FHLBsea.com, or other comparable service selected by Lender. This definition of Ninety Day FHLB Rate is to be strictly interpreted and is not intended to serve any purpose other than providing an index to determine the rate used herein. It is not necessarily the lowest rate charged by Lender on its loans. If the Ninety Day FHLB Rate becomes unavailable during the term of this Promissory Note, Lender may designate a substitute index after notifying Borrower.

“Ninety Day LIBOR Rate” means the rate per annum quoted by Lender as its Ninety Day LIBOR Rate based upon quotes from the London Interbank Offered Rate from the British Bankers Association Interest Settlement Rates as quoted for United States Dollars by Bloomberg or other comparable services selected by Lender. This definition of Ninety Day LIBOR Rate is to be strictly interpreted and is not intended to serve any purpose other than providing an index to determine the interest rate used herein. The Ninety Day LIBOR Rate of Lender may not necessarily be the same as the quoted offered side in the Eurodollar time deposit market quoted by any particular institution or service. It is not necessarily the lowest rate at which Lender may make loans to any of its customers, either now or in the future.

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Payment Terms

Interest is to be paid in arrears commencing November 1, 2011, and on the same day of each month thereafter.

Principal outstanding is to be paid in 36 equal monthly installments commencing November 1, 2011 and on the same day of each month thereafter through the Maturity Date.

All outstanding principal, unpaid interest and all other amounts due under this Promissory Note or any of the other Loan Documents shall be paid in full on the Maturity Date.

All payments shall be applied (a) first, to reimbursable fees, late charges, costs and expenses payable by Borrower under this Promissory Note or any of the other Loan Documents, (b) second, to accrued interest and (c) the remainder, if any, to principal.

Interest shall accrue from the date of disbursement of the principal amount until paid, both before and after judgment, in accordance with the terms set forth herein.

Interest Rate Election

On the Effective Date, Borrower shall elect for interest to accrue based on either the Ninety Day LIBOR Rate or the LIBOR Rate for a specified Interest Period. Upon the expiration of any elected Interest Period, the interest rate hereunder shall automatically convert to one based on the Ninety Day LIBOR Rate unless Borrower gives three Banking Business Days prior written notice to Lender to renew the LIBOR Rate for a specified Interest Period; provided that no Event of Default has occurred and is continuing at the time of any such election.

Provided that no Event of Default has occurred and is continuing at the time of any election, at any time that interest is accruing hereunder based on the Ninety Day LIBOR Rate, Borrower may elect to convert the interest rate on the entire outstanding principal balance hereunder to one based on the LIBOR Rate for a specified Interest Period by giving three Banking Business Days prior written notice to Lender of such election.

Any election to convert to an interest rate based on the LIBOR Rate for a specified Interest Period may not be changed after notice is given by Borrower hereunder without consent of Lender until the expiration of the selected Interest Period.

Interest Based on Ninety Day LIBOR Rate

Interest based on the Ninety Day LIBOR Rate shall be calculated as follows:

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Interest Based on LIBOR Rate

Interest based on the LIBOR Rate shall be calculated as follows:

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Prepayment

Borrower may prepay all or any portion of this Promissory Note at any time without penalty or premium; provided, however, that in the event of any voluntary or involuntary prepayment of any LIBOR Rate based balance prior to the end of an Interest Period, Borrower shall make Lender whole and Borrower shall pay to Lender all breakage costs incurred by Lender in connection with such prepayment and compensate Lender for any actual out-of-pocket loss suffered by reason of such principal payment not being made at the end of the Interest Period or as scheduled. Such costs and losses to Lender shall be limited to any loss or breakage costs arising from the re-employment of funds at rates lower than the rate provided by this Promissory Note, cost to Lender of such funds, any interest or fees payable by Lender to lenders of funds obtained by them in order to make or maintain the loan evidenced by this Promissory Note and any related costs. Unless specified otherwise by Borrower, (a) prepayments of principal shall be applied first to outstanding LIBOR Rate based balances, and (b) prepayments of principal applied to LIBOR Rate based balances should be made in the principal amount equal to the aggregate principal amount of the LIBOR Rate based balance, if any, that has an Interest Period ending on such date of prepayment, and so long as no Event of Default has occurred and is continuing, Borrower may, at its option, defer the balance of the prepayment to be applied against any other LIBOR Rate based balance until the next following Interest Period applicable to such LIBOR Rate based balance; provided that cash in an amount equal to the amount of any prepayment so deferred shall be deposited in a cash collateral account maintained with the Lender.

Any prepayment received by Lender after 2:00 p.m. mountain standard or daylight time (whichever is in effect on the date the prepayment is received) shall be deemed received on the following Banking Business Day.

General

Any prepayments shall reduce or excuse the last installment payments owing. All scheduled installment payments shall remain due and owing as scheduled until all outstanding principal has been paid in full.

Upon default in payment of any principal or interest when due, whether due at stated maturity, by acceleration, or otherwise, or upon the occurrence and during the continuance of any other Event of Default, all outstanding principal shall bear interest at the Default Rate.

This Promissory Note is made in accordance with the Loan Agreement and is secured by the Collateral identified in the Security Agreement (as defined in the Loan Agreement).

If an Event of Default occurs and is continuing, Lender shall have all the rights and remedies provided in the Loan Agreement, including, without limitation, provisions relating to expenses.

This Promissory Note shall be governed by and construed in accordance with the laws of the State of Utah.

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Borrower acknowledges that by execution and delivery of this Promissory Note Borrower has transacted business in the State of Utah and Borrower voluntarily submits to, consents to, and waives any defense to the jurisdiction of courts located in the State of Utah as to all matters relating to or arising from this Promissory Note. EXCEPT AS EXPRESSLY AGREED IN WRITING BY LENDER AND EXCEPT AS PROVIDED IN THE ARBITRATION PROVISIONS IN THE LOAN AGREEMENT, THE STATE AND FEDERAL COURTS LOCATED IN THE STATE OF UTAH SHALL HAVE SOLE AND EXCLUSIVE JURISDICTION OF ANY AND ALL CLAIMS, DISPUTES, AND CONTROVERSIES, ARISING UNDER OR RELATING TO THIS PROMISSORY NOTE. NO LAWSUIT, PROCEEDING, OR ANY OTHER ACTION RELATING TO OR ARISING UNDER THIS PROMISSORY NOTE MAY BE COMMENCED OR PROSECUTED IN ANY OTHER FORUM EXCEPT AS EXPRESSLY AGREED IN WRITING BY LENDER.

Borrower and all endorsers, sureties and guarantors hereof hereby jointly and severally waive presentment for payment, demand, protest, notice of protest, notice of protest and of non-payment and of dishonor, and consent to extensions of time, renewal, waivers or modifications without notice and further consent to the release of any collateral or any part thereof with or without substitution.

[Signature Page(s) Follow]

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IN WITNESS WHEREOF, this Promissory Note has been executed by Borrower as of the date first written above.