From my understanding this is no longer a guaranteed (emphasis on the word guaranteed) program like the original Texas Tomorrow/Texas Guaranteed Tuition Plan that we (my parents) could buy 10 years ago.
That plan ended up costing the state a lot of money considering that education inflation was around 7%.
I would do some research on the plausible risks. I cannot attest to the validity of the claims in the article below but it could possibly help you to make a more informed decision.
http://www.bankrate.com/finance/college-finance/college-529-prepaid-tuition-plans-at-risk-1.aspxFrom the website
"Is the Texas Tuition Promise Fund guaranteed by the state of Texas?
While the Texas Tuition Promise Fund is not constitutionally guaranteed, Texas law requires all Texas two-year and four-year public colleges and universities to accept Texas Tuition Promise Fund Tuition Units as payment for the applicable portion of tuition and required fees....
...The Contracts are not deposits or other obligations of any depository institution. Neither a Contract nor any return paid with a refund is insured or guaranteed by the FDIC, the state of Texas, the Texas Prepaid Higher Education Tuition Board, any other state or federal governmental agency or Northstar Financial Services Group, LLC or its affiliates. The Contracts have not been registered with the U.S. Securities and Exchange Commission or with any state.
Purchasers should carefully consider the risks, administrative fees, service and other charges and expenses associated with the Contracts, including plan termination and decreased transfer or refund value."