Just got a 2006 Nissan Xterra for my daughter as a replacement for her 2001 4Runner that was totaled last weekend. After scouring the Southeast for a 4Runner in good condition I gave up and went looking for something else. Added an external transmission cooler, the factory coolers in the radiator have a history of mixing coolant in the transmissions, flushed the tranny, services it and prepped it for going to Colorado. That 4 liter engine has some beans compared to the Toyota, suspension is very good and it has stability control and ABS. Hope it does as well as the Toyota did for her.

I ran an 01 for years,never gave me an ounce of trouble.If it hadn't rusted to hell I'd probably still be running it.

My big sis had an '06 or '07 that gave her trouble. Mostly electrical, some tranny problems, all under warranty. It was at the dealer more so than not. I've heard mostly good things about X-Terras, maybe her's was just a lemon.
She ended up getting a 4-Runner last year.

I've got an '07 Frontier with the 4.0, and it's got some pep to it, rated for 6500lbs. towing, not that any sane person would do that (it ain't the go, it's the whoa!, and it only weighs 4000 lbs itself). I haven't had any issues to speak of, the fuel sending unit went out, and it was replaced free AFTER the warranty ran out, I guess there was a stealth recall on certain models.
But I can't think of any vehicle I've been happier with.