If you're going to tow something heavy, go ahead and add a tranny cooler. On a previous vehicle, I bought a kit at my local performance shop, and installed it in less than an hour with basic tools. Unless you install it wrong, it will only add life to your tranny. But if you really want to keep your tranny living for years, change the fluid every year. Not difficult to DIY, and not real expensive.

The new X should have no problem towing. My 2000 Nissan Crew Cab with its tiny 3.3L (170 HP, 200 ft-lbs) was also rated at 5000 lb towing capacity. It had no problems towing my camper, 4 people, a topper, and a bed full of equipment... oh, and a kayak on the roof.

As for trim model, well, that's a tough call. My dad opted for an 05 X with the S trim. I went for the SE. I do like the upgraded stero, trip computer, the power package is included ($900 option on the S), fold-flat passenger seat, but I could care less about the 17" alloy wheels! Both the S and SE 4x4 models come with ABLS (4-wheel Active Brake Limited Slip), which should help prevent getting stuck by applying the brake to a spinning wheel.

The locking rear diff on the OR package is nice, but the ABLS "should" do a pretty good job of mimicking that action. For all out rock crawling, you'd want a locking diff. Skid plates are a plus, but I don't think the factory ones are worth writing home about. Aftermarket ones are available. The OR comes with upgraded shocks, woo-hoo. The big benefit I see is an extra inch of ground clearance. Might be able to tighten the torsion bars and change the rear shackles... as done on earlier Nissans to gain a little extra clearance without spending money for a lift kit.

Whatever you buy, you'll love it. If you want to do some serious off-roading, you'll likely get a lift kit, get better skid plates, swap out the plastic bumpers for steel and add a hoist, and add bigger tires. No factory off-road trim is ever sufficient for anything serious.

Just my $.02