With Cordura outer fabric and internal hardcap protection the 661 Comp AM Knee Guard offers great protection for aggressive trail or all mountain riding.
Ended up going OTB wearing these and they protected my knee from the initial impact, but slid downwards as I ended up with my head pointing down hill and rolling. I've got rock road rash all over my knee cap. These seem to be sufficient for XC/maybe mild dirt jump, but rocky tekno / REAL all mountain riding is a no go. Ill stick to my 661 comp full knee/shin hard plastic armor. Maybe EVO's are next.
I love these pads. I only have one 2hr+ ride in them, but I'm amazed at how comfortable these are. I forget they are even on during long uphills, and push it a little harder in the downs knowing I have knee protection. Exactly what I was looking for as an everyday aggressive free-ride pad. No idea how they hold up in an actual crash just yet. Being that its currently winter, I have no heat complaints. Ventilation seemed fine but wont really know till summer.