I have no problems with mine off-road.
Check out this pic... full tuck and full extension (although no air) and the body is perfectly level. Nice...nobody spilled thier drink.
Couple things about offroading with the 03+.
Like all SUVs today, the running boards are too low. Even on the FX4 or NBX packages. Remove them if you go in real rough stuff. I bent mine the first time out. I can't remove them because my wife will yell at me.
IRS is great for washboard, washed out & fire roads. MUCH better than a solid axle but kinda crappy for crawling rocks and real technical stuff. A solid rear axle does MUCH better.
I think the stock tires & the low departure/approach are the biggest limiting factors.
We wheel a lot here in Hawaii. Some of the best beaches in the world are only accessible via 4WD vehicles.
I've gotten everywhere everyone else has, unless I'm tryin' to follow a tricked out Jeep. I've never been stuck.
Also, the LS unit is mine is cherry! Works PERFECT! Maybe looks for an 03 or an 04+ that has a LS. They were standard in 03.