anything over 295 is width will be outside the manufactures recomendation. which people will argue as not big deal. I don't pretend to design tires in my spare time so I just run what they recomend.
people run wider but I would buy a wider rim if I wanted a wider tire. when you mount a wider tire on a narrower rim it kind of necks in anyway. .
the most comon sizes in actual street tires is going to be 275, 285, 295.
I would go as wide as redomended and that is 295. I got 285's because I wanted BFG kdw-2's and they were out of stock on the 295's at the time.