my best ally was Baron French at Metro VW in Irving. my car is modded all up, and he still took perfect care of me my whole warranty including getting me a free loaner every time. when i first met him i gave him a tour of my car and all its mods.. i was totally honest with him hoping to avoid surprises on both our ends, and that seemed to work.
Kenny Smith at Boardwalk is also great, but i didn't have much experience with him, although he did replace my leaking cats at 65k while i had a combo flash (ECU & DSG) and a CBE... no complaints from him, and he threw in a loaner as well.
park place and rusty wallis didn't want nothing to do with me.
just my experience, hope it helps. if you see Baron, tell him i said hi (David with the grey modded mkV R32).