I have been running the Rusty's 4.5" spring pack kit and BFG MT/R 32x11.50's for about 2 years. I regeared to 4:10's and that's pretty much it. I have alot of extras, but as far as drivetrain goes,I haven't gotten too extensive. The lift and tires compliment each other well with great articulation and rough t/r capabilities. I'm very pleased with this lift and it takes me every where I want to go. I may eventually up grade to a 6" and 33's, but for now I'm very happy. I agree that 8"'s and 35's or larger looks good and is much more capable of doing stuff mine can't, but like I said, mine takes me every where that i want to go. Like what has been mentioned earlier, you need to look at the t/r you want to cover, but you also need to consider your experience in 4x4 driving you have. Nobody wants anyone to get hurt on the trail because they have more vehicle than they can handle. You can always upgrade later, but if you role your Xj, you have to start all over again, if your not hurt too bad. I don't mean to preach about saftey, but after all, your health determines YOUR capabilities.