I think it depends on how "rugged" of a car you are looking for. Liberties and Grand Cherokees and Commanders are all unibody designs that die-hards basically will shun as being soft simply for the fact they're not body on frame (BoF) vehicles. Xterras, FJ Cruisers, and Jeep Wranglers remain steadfast with the traditional "body on frame weighs more but you get a better rugged vehicle" approach.
A few years ago, a body on frame Durango outperformed the unibody Grand cherokee... in combined evaluation (on road and off road), simply because Jeep hadn't worked out how to best utilize a unibody effectively. Assuming your tires aren't blatant 4x4 mudders most BoF are actually quieter inside for a given price point. Compare a unibody Toyota Sequoia to a BoF 4Runner and you'll see how the 4Runner just seems like a better ride (at a better price too).
Personally, if you just need a versatile off-roader and don't really want to keep it for 10 years, let me know and I'll send you a coupon to get a Liberty at like 4% below the invoice. Liberties are about to get replaced, with the new versions being way better than the outgoing platform. If you read that the forthcoming Liberty is "just the same as the old one with marginal changes" then you're reading a bunch o' lies.
But, if you want the most capable rugged mini-SUV that you can get today, I think you'll be hard pressed to pass on that FJ. Toyota just makes some perfect cars. it's freaky. Xterras are pretty nice too, although they are getting a bit dated as well. Don't bother with the Element, Rav4, CRV, whatever soft-roaders if you're valuaing any sort of ruggedness in favor of slightly better fuel economy.
