OP, it sounds like you got a pretty sweet deal with either.
Couple questions
How much is the study abroad and research stipend ? Do you have to do research at UH with that scholarship ? What do you plan on majoring in ?
Couple of observations: my friends who came from UTD had a good time and education. The ones that were premed had a good experience and were quite successful with UTD. UTD has some research going on on campus though since its not a tier 1 I'm not sure how ubiquitous it is compared to UH. However UTD has some partnerships with UTSW including a bs to to route and a close relationship with their admissions ( when I was a wee lad I had met with one of the admissions doc and he kept pushing for me to go to UTD vs another big state school) . the cash stipend is big especially if you live at home. UTD is also in Richardson is a nice area compared to the area surrounding UH( third ward)
UH is good school as well. Being Tier 1 means plenty of research opportunities and money. Probably more study abroad and research diversity . I cannot comment on the partnership of UH and Texas Medical Center or know much about UH premed but being in the same city and general (20-25 min) area of the TMC is big for potential researching and networking opportunities. I do known that last time I looked UH was on a plus minus grading system meaning it's easier to not get a 4.0 beacause of A- 's etc. Dunno how UTD grading is done .
Good luck. You'd get a great education no matter what. The biggie is doing well nonmattet where you are. Try not to take a bigger load than you can handle and get involved with community service, shadowing, research , and other extracurriculars/activities earlier than later to spread out the wealth and time.