RE4.5" kit with 32s looks pretty good - mild enough that with stock flares and all it looks like a stock cherokee but awesome.
I was going to go with a 3.5" kit but friends convinced me to go with the RE5.5" superflex kit with 33s. It comes with a few extra pieces than the 4.5" kit and gives you an extra inch to play with when loading down your vehicle with bumpers and skid plates. The only thing it was missing is a drop pitman arm but since I don't know what driving a similar xj WITH a drop pitman arm feels like, I don't know if I need one lol.
Just so you don't forget, you will need to get a SYE kit and a new driveshaft, new rims with backspacing, maybe new motor and trannie mounts if it's an older model (mine's a '93 and motor mounts were shot). Regearing? Locker? Don't forget about shocks...the kit doesn't come with those.
The one thing I wasn't happy with when I did my lift was the steering. Having bigger tires with stock steering sucks and I feel it is unsafe to drive on some roads just because it feels sluggish and there is a dead spot. I've read of stuff to fix that but a year later, and I'm finally getting new steering altogether.
Another issue with my RE leafs is they start splaying out to the side...a year after lifting my vehicle the bottom 1-2 leafs on each side were sticking out about an inch. This was solved by loosening the ubolt brackets slightly and hammering the leafs back in. Also when installing the drop brackets parts of my frame rail were out of shape so it made putting them on a pain...first drop bracket took me 4 hours over two days (frustrated n had to quit the first day) and second one went on in 30 minutes.
If you want the stronger (29 spline) 8.25 look for XJs '97-99, I believe. I like the look of the pre-'96 models however I bought an 8.25 from a newer model for the slight strength increase.
I am pleased with Rubicon Express' quality and their customer service is great...called them with a problem/clarification of the instructions and they were able to answer it quickly and professionally. Also the instructions were very clear since I was able to put the lift on mostly by myself with no previous experience. You'll just need a friend or two when reattaching the axles.
In a nutshell - two thumbs up for RE. If I were to do it again with the knowledge I have now, I would piece together my own kit for cheaper (used parts, too). For my first time lifting having a kit with instructions was nice. I just have 4 bolts left over in a sealed bag...still don't know where they go :shhh:
For reference - 5.5" RE kit with 33s and lots of trimming: