a lot of ppl confuse lipping and guard rolling or flaring. As I understand it, lipping is only flattening the inside of your guard lip, no paintwork will be affected or cracked. Guard flaring on the other hand will involve heating the panels and rolling them out...thts when u run the risk of paint cracking.
My Works were 18x8 +35 still had plenty of room to move! I'm now running 18x8.5 +30 at the fronts which is the most i'd recommend before you start needing camber adjustments or guard mods to fit.