I have nothing but good things to say about these pads. The fit is great they are super snug and don't move yet they are not so tight that they cut the circulation to the rest of your legs (ya i have had knee pads that do that.) I have taken some nasty falls with these and they have taken the whole impact. I love how the Pads are not a hard plastic piece but instead are a solid foam that seems to turn hard when taking a big hit.
To sum it all up... buy them! for the price you cannot get anything better! I am 6'4 and 135lbs. I got the Small because I am a twigg.