My measures were 19in and 16.25in for above and below the knee. I first ordered the mediums, they fit but they were a bit tight since they stretched to the upper limits of the neoprene. I ended up having backcountry send out the large size and they fit great! As always thanks for the awesome service!
The pads are excellent and comfortable once you get the right size. The 3DO protection has worked great. I have taken a couple of falls on these pads and they still look new. I have no doubt that they will hold up. If you haven't read up on 3DO do a youtube search for it and you'll see how well it absorbs the impact. Even after these pads wear out, I've read reviews saying that I can get a pair of the 661 Riot Knee Pads and just swap out the protection with the 3DO! Hope this helps!