If you plan to do a competitive fellowship, expect to work during your residency.
The idea of landing into a cush IM program and then expecting to get a competitive fellowship seems absurd. At least a PD for a competitive fellowship will find it hard to take you seriously without demonstrated clinical competence. Personally, I'd rather and am actually in a Houston program that prepares me to handle any kind of of IM patient that walks through the door than one that makes me wonder what kind of actual training I received.
Fellowship lists are readily available at the two main Houston programs:
Baylor College of Medicine
http://www.bcm.edu/medicine/residency/?PMID=7021
UT-Houston
http://www.uth.tmc.edu/schools/med/imed/residency/match-list.html
Now it's just a matter of time before someone brings up the old BCM-Methodist split and why UTH MUST therefore be superior. I'll throw in the possibility of a Rice Univ.-BCM-Methodist merger to spicen up the debate, if it happens.