Try Mikes Flying Service in Terrell, Texas (KTRL) as they have really cheap rates and I have known Mike for a while. I met him when I worked the line in Tyler, and he cranks out ratings pretty quickly. His DPE is the nicest, and most fair DPE I have taken a check with. He gave me my PPL and my CMEL. Mike is real laid back, his family owns the FBO there, Terrell Aviation.
Mike's Flying Service, Flight School, Terrell, Dallas
He has PA-28, PA-34, C-152, C-172, Eurcoupes (he has like 14 I think?) and a few Apaches.
He's pretty cool, low key, low stress, and fun to work with. They have a CATS testing center in house, which is cool.
As far as US Aviation, I have friends who fly for them and I was flying with a guy in a C90 to Florida last week who was one of the first CFI's back in the 1990's there. I have no experience with US Aviation, but if you want I have 3 contacts for CFI's who work there.
I flew with ATP in Addison and Arlington, which is cool....but comes with the typical flaws of most big flight schools.
Hope this helps.