If you don't plan on lowering it (I don't), is there any reason to stay at the 30.7" max diameter? I was actually thinking about going with 21"x10.5" with 315/40 rubber, which would be about 30.9". I know 22"x10.5" with 305/35 is the popular choice, but I actually want a little more rubber on there for a little bit softer ride, but also since I don't plan on lowering it "fits" better than the 22" option (at only 30.4" tall, there is a bit more gap between the tire and fender).