I weigh 148 lbs (137 fighting weight, but I've been in winter form all year) and run my tires at 25 psi front and back. I'm on Hutchinson Toros mounted tubeless on the Shimano XT 29er UST wheelset.

I'm a newb so I wouldn't pretend to know any better; but I like having tires that conform to the rock gardens—especially when climbing. I ride fast but don't know how to jump or do other crazy stuff, so for the most part I don't take hard hits.

I rode tubes for a several months: 25/27 psi (front/rear), Nevegal 2.1 in front, Small Block 8 2.1 in the rear, and using Performance Ultra Light tubes. I pinch-flatted once from a rock I didn't see.

Before I was serious about MTB I had a steel hardtail that ran a pair of Panaracer Fire XC Pro 1.8, Performance Lunar Light tubes, 25/27 psi and I never pinched on those in two years.