I have the Rough Country 4" lift kit. I used everything that was in the kit (tcase drop and brake line relocation brackets) I've had no problems yet. But if you were going to wheel it hard I would suggest longer brake lines. I haven't seen mine at full flex, but they're probably pretty close to tight.
And I like the RC lift. Mine doesn't ride smooth, but I think that's because of the stock shackles being rusty. That being said I think it's a good lift for the price. But I bet that the more expensive lifts ride smoother.
But who wants that? It's a jeep, it's fun!