I wear knee and elbow pads on most MTB rides since buff singletrack is a thing of the distant past for me. My goto pads are taking a beating just from regular wear and tear of the elastic sleeve. They’ll need replacing in 2012. I found these G-Form low profile pads online and given the modest cost I may give them a shot. They don’t offer as much protection as my other pads, but for a lot of the riding I do which is just rocky/rooty techy XC stuff they may be perfect. They also look like they’ll keep my joints warm which in BC is another great reason to wear pads!
These pads got a Best Product of 2011 nod from PinkBike. So they probably don’t suck.
The SixSixOne pads I am currently using are shown below back when they looked nice and new. They are a great pad with a decent amount of protection for their size and don’t really get in the way when I ride, but at the same time you can’t help feel a little gladiatorial with them on…=-)