I did a 4th year sub-I there in "TASC" which is the Truama and Emergency Surgery service and had a good time. It's a bit bizzare at good-sized county hospital to being seeing appys, choles, amputations, abscesses, blunt trauma, and penetrating trauma all on the same call night. This apparently is one of the new 80hr/week changes and makes for some pretty busy calls and long lists, but the great thing is that there is almost always an OR running (sometimes up to 3) and the residents seem to get great OR time.
I'm biased, since I want to do trauma, but I thought it was a very solid program. As County hospitals go Parkland offers a pretty good environment. Great resident OR time (at least on this service) and it's a pretty big program (in the high teens of categorical positions/yr if I remember correctly).
Er, I mean it's a poor program and no one else besides me should apply... Seriously though, if resident autonomy and trauma are important to you I would consider it heavily. It is high on my list.
Dallas is really not "Texas" as I think of it. I've lived in DC, Boston, and LA and have spent a decent amount of time in New York, Chicago, and Seattle and found it to be more cosmopolitan than I expected. While it lacks some of the natural beauty of a more coastal region and it is ridiculously hot and humid in the summer, it seems socially pretty reasonable (says a white male). Fair amount of young professionals, a decent nightlife, cheap housing, a passable array of ethnic restraunts, etc.