You should go to the "Widening Wheels" thread and not chat first off:
#/f/showthread.php?t=327620
Second, this is a very vague question that you should already have the answer for, if you are running any kind of business. No one knows what size is most preferable. It depends on whose buying them. My Blitz will be rebuilt with 5" and 6" lips but that's too aggressive for a lot of people. You should have them painted and polished regardless.