Just installed my RC 3.5" lift and I'm currently running 31X10.5's... They look a little small but they'll work at least until I get the $$$ to buy 32'sX12.5.
Haven't had the opportunity to trail ride with the new lift, but I plan on taking a short ride tomorrow to see how everything is working. There are several people within our local jeep group that run some kind of RC set up and they're all pretty much satisfied with what they have - this is why I went with RC. You'll find many different opinions regarding lifts on this forum - which is the beauty of it all.