I did med school in San Antonio. From what I know, the program in Austin is not the best. I don't think it routinely fills and of course, since it is a private program, you may suffer from a lack of autonomy. Living in Austin though, would be the biggest bonus.
UTHSC-San Antonio is a fairly strong program academically and the night float system works okay.
You can get some great cases up from the border with Mexico. However, the hospitals don't support the housestaff very well and the facilities are fairly crummy. The ability to speak spanish fluently is an important trait you might want, since taking histories through a translator is painful.
UTMB is much like San Antonio in structure. The predominant patient care there is indigent...usually from many miles away, which makes disposition a hassle. Galveston is by the ocean , you can give it that....but near an extremely polluted port of Houston.....you can swim in the water....at your own risk
UT-Houston was on probabation from the RRC when I applied. I turned down my interview. I think the program has undergone some restructuring, but I think Baylor has a better IM program, although the residents I met there were on the obnoxious side. The predominant comment I heard from them was how much money the program had and all the amenities.
As for Private programs, BUMC in Dallas is really cush....but again, you will suffer a lack of autonomy. UTSW is a top program and attracts a more gung-ho type. Parkland is an incredible hospital.
Thats the short of what I know. Texas is nice and inexpensive...just hot. Houston is almost unbearable in the summertime and if you live anywhere near the TMC, you will be completely devoid of any contact with nature....Houston is the quentessential definition of urban sprawl. San Antonio, Dallas aren't much behind. Everything is bigger in Texas.....just not always better.