Sorry that took so long- Just enjoyed a long weekend with my son. We use Sherwin Williams (40% of domestic products are factory S&W) It is purely a numbers deal with us. Trying for good matches, with the least hassle, for the most vehicles, for the best price and longevity(we guarantee all work for the life of the vehicle so it's gotta last). PPG is the easiest system,for me, but a bit pricey(and their clear stinks (IMO)) Dupont is ok- real nice Tri-Stage stuff clear is good (I got a 12 gal. case of ol' 9600 clear stashed for when I do my own stuff, you shooters know what that is) but is a bit expensive, fragile,and their product support sucks-we threw them out---- These choices constitute probably 75 or 80% of the professional shops out there. You will have to make the guess.