So, the big 2 are UTSW and Baylor obviously. UTSA is an up and coming program, and may join the top of the pile soon (some folks think they may have already passed Baylor, but I think this is unfair and an overreaction to their "troubles"). Still, it's interesting gossip and illustrates outside perception, which is almost as important as the "truth" sometimes.
I have heard good and bad things about UT-Houston, Scott and White, UTMB, and Tech. I think they'd rank in about that order, but when you're dealing with the vast morass of "mid-tier" university programs, they're really all about equal; you can make slight adjustments up and down based on your preference.
Baylor-Dallas, UTSW-Austin, Presbyterian, Methodist Houston and Methodist Dallas are all community programs, I believe, and thus rank "lower". Though if you have specific goals they can be very good choices (i.e. doing a Baylor residency and staying in house for their very solid GI fellowship). It will be interesting to see where the UTSW-Austin program goes; this is the first year of the affiliation, and the infrastructure and track record are just not there yet. It would be sweet for future folks to have a solid program in that city, imo.
I think the tiers here are pretty cut and dry. Beyond that, assigning specific numerical ranks to programs without knowing the personal preferences and career goals of the specific individual involved - whether in Texas or elsewhere - becomes a fool's errand (Though that doesn't stop people on this board from trying
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