265's will have a very very slight stretched look. The tires will have a little curve.
275's should fit like a glove.
285's should make the tires bulge at the sidewalls just a hair. Doesn't look bad in my opinion. But if I were to run 285's in the rear, I would want the rims to be 10.5 inches wide or 11 inches, because I like that very slight stretched look.