These are a good fit (small size, I'm 180, 5' 10") and comfortable under my jeans. Combined with my Sidi Fusion boots my knee and shins are protected. I had an earlier version of these pants and they lasted a good five years until the fabric started to tear around my feet and lower shins. They probably would have lasted longer if I took greater care when removing them.
I have yet to test these in an 'Off' and have no plans to do so in the immediate future : ) but I believe they would offer excellent coverage.