I'm an Tech/El Paso grad, so that's what I know best, but here's my $0.02 on those programs.
Houston - had a couple classmates of mine who matched to Houston, but it was at the bottom of my match list because at the time they had a very poor RRC review and IIRC had their accredidation pulled revoked briefly before being reinstated the next year. To my recollection there were a variety of factors involved, but the main problem at the time was very poor leadership and high faculty turnover. This was 6 years ago or so, so things may have changed drastically. The classmates I knew there seemed pretty happy though.
Dallas - At the time I applied was a very new program, with all those attendant worries. Those should mostly be over now, but you still have to fight with surgery (who ultimately runs the ED) and they're still a division within the dept of surgery IIRC. Parkland is going to be a high volume, high acuity, lots of pathology hospital, so you'll defiintely see a lot there.
A&M - aside from being an Aggie program, the guys from Temple seemed very happy with it. Nice hospital. Temple is one of those sit down and read programs, as their patient volume doesn't match up to any of the others mentioned. It depends on what your style of learning is like. Some people really do well in that setting. "At least we're not far from Austin" was the most common refrain I heard from those guys.
El Paso - I've spoken at length about my program elsewhere, so I'll be brief here instead. Good program, strong clinically, better be willing to learn Spanish, as about half of your patients will be Spanish-speaking only. Last had an RRC review during my senior year 3 y ago, and it was a solid review for us. It's the oldest non-military program in the state, so we've got grads everywhere (including the PD at Dallas, who's a super nice guy).
I'm no longer in Texas, so I'm a little out of touch with the current status of these programs. Take c one grain NaCl prn.