265/75/16's with no lift. I had the stock 225's and went to the 265's. Here's my summary:
-Ride & handling is about the same.
-265's fill out the wheel wells really good with No rubbing even at sharpest turns.
-Gas mileage dropped by 2 mpg.
-I got a 1"+ lift just from the tire size change.
-Speedo was off about 5 mph from going to the bigger size, but I got it calibrated at the dealer for $60.
My Jeep is more of a daily driver so I am very pleased with the 265's.