Welcome to SCCX...a great group of members/friends here.
As far as your lift question, take a spin through the Display Case area here to get the specs on some of the members rigs. There are photos and testimonials for a variety of suspension lift installations.
My personal experience has been with PRG Products, and their quality is unparalleled. Their customer service went through some growing pains (keep in mind the Xterras are a purpose built SUV, not meant to compete with the flourishing Jeep aftermarket), but has improved in recent months.
I installed both a PRG 2" spacer/shackle lift, upgraded a year later to the PRG Advanced 4WD lift kit (3-3.5" of lift), and then in August of 2012 did a Titan Swap suspension conversion.
The 2" PML (poor man's lift) was a great, inexpensive option while I figured out what the other members were running successfully. It carried me through Big Bear, two trips to Moab, Utah, many trips to Anza Borrego, etc. This kit gave me the fender clearance to run larger tires (285/75/16's, or 32" tires) as well as a little more rear articulation with the rear sway bar removed. The on road performance was not compromised, except for a bit of what is referred to as "coil bucket" contact over speed bumps.
This lift cost me $278 delivered, and I installed it myself in about 5 hours. The extended time was due to several factors, inexperience, several over torqued nuts/bolts by Nissan, and completing the task solo. That could have been cut in half with another person to help and air tools. As a side note, Greg Gagnon, the owner of PRG products, answered his phone that Saturday to help a noob in need (me
) answer a question about his shackles. This was in April of 2010.
There are many lift manufacturers on the market now, Nisstec, Old Man Emu (OME), 4x4 Parts.com, etc. Opinions are like elbows...everyone's got them...
Check out the boards/threads here and also over at TheNewX.org.
Good luck, and very much looking forward to meeting you on the trail soon.
John/GhostX