Very nice knee guards. Very comfortable. D3o padding is as good as it gets, and it is rare to get D3o at such a good price. After riding in them a few times I am very happy with how comfortable they are. They stay put and don't slide down. Sizing is good - the fabric has a lot of stretch.

Stay in place, comfortable. Knock on wood, have not crashed yet to test durability.

I only wear these for MTB, but they are super comfortable and stay in place well when riding. They have plenty of stretch and it's nice having a good guard with D3O armor! They're worth getting if you're looking for a good set of knee guards.

I wore the Mountain Bike MSR Knee Guards for three rides totaling 37 miles. Shortly after beginning each ride I stopped thinking about them and forgot I had them on. At the end of the rides I noticed that they had not slipped and were still properly in place. I have not yet fallen with them on so I cannot say how well they protect, but I'm hoping the D30 material does its job, but more hoping I don't fall. I also measured my legs about 6" above and below the knee and I was in about the middle of the sizing chart for the large. So it seems that the sizing chart is realistic.

So far so good with these, they are comfortable and seem to stay up well.