SRD and especially Hardin House will be MAJOR pluses if you do happen to live in one of those. Not necessarily because sororities think the girls who live there are better, but because you'll be meeting/mixing with girls who are pretty well prepared for UT recruitment. If that makes sense. Most (if not nearly all???) of the girls in HH for example (I can speak to that more than SRD because I have friends who lived in HH) go Greek.
But you should know that getting into those dormitories is pretty difficult. You have to work your connections.
I don't think, though, that sororities will look down on you if you do not live one of those places. They surely understand how hard it is to get placed in those dorms - they're really high demand!
MANY MANY MANY girls who do not live in HH or SRD find their homes at UT!