Lot's of doctors across the US (and Thailand) do body sculpting liposuction with or without a buff lift but not all do trans patients. There are a whole bunch in the LA area who work with trans people, Dr Z (obviously) and others scattered around the place. THere are so many you would have do the research yourself. In some some ways choosing a surgeon for this is much of a muchness so long as a) the surgeon has worked on lots of trans people before AND knows exactly what they are doing b) is medically qualified c) you like their work d) you feel comfortable with them doing the proceedure.
It is really important to ask how they do it, what sort of fat cells they use and all of that. Some techniques are better than others. That being said the overall "sucess" of it depends on how much fat you have to sart with, how much fat you can retain, your doctors and of course your expectations!
I don't know if it has been mentioned before but Dr Chugay in LA does solid silicon implants. I have heard mixed reports about his ability as a plastic surgeon, but the photos I've seen looked good. I haven't heard anything from any patients directly about silcone implants though. He does good tits too (Dr Z generally -but not always- does terrible tits if you are thinking of getting a BA with him).