Ofcourse I find the answer right after I post this:
What can I do if there are units left over?
If you have accumulated more tuition units than you need to cover tuition and required fees, you can:
Change the Beneficiary of your contract to a Member of the Current Beneficiary’s Family. See the Plan Description for details and consult your tax advisor to determine whether such a change creates a taxable gift or other adverse tax consequences for you or your Beneficiary.
Transfer the Transfer Value of unused tuition units to a 529 college savings plan, such as the Texas College Savings Plan® so that the money can be used for graduate school tuition, fees, books or room and board. Transfer Value is limited to the lesser of a) the costs the Tuition Units would pay to a public in-state college or university, or b) the original purchase price of the Tuition Unit plus or minus the Plan’s net investment earnings or losses on that amount.
Request a Refund of unused tuition units. See Cancellations and Refunds for information on how refunds are calculated. Federal income taxes and an additional 10% federal tax on the earnings as well as any state or local taxes may apply.
Anyway, I am still looking for opinions on this and other 529 type plans.