100%, absolutely, STAY AWAY from Calmini.
The Kern County DA's office is filing a lawsuit against Bakersfield-based company, Calmini Products for unfair and deceptive business practices after numerous customers complained they never received their products after paying for them upfront.
www.turnto23.com
Shipping sucks, but these guys build quality parts, and you are going to get them:
Nissan - Suspension - Suspension Lifts & Lift Packages - Xterra - 2000-2004 Xterra Suspension Lifts & Packages
www.4x4parts.com
I wouldn't worry about a lift, unless you plan on going rock crawling, and even then, you're not going to get too much. You can lift the suspension about 1.5 inches, and then do a 2 in body lift, and stuff 33's under there, but that's pretty much as far as you can take it, unless you SAS.