Outstanding quality knee-pads that allows for maneuvering and does not hinder your movement. Running with these go fine and they do not slide and do not lower at all. A bit stiff but that may cease on regular use.
They do look a bit sci-fi, but are practically great and less bulky than the standard ones.
The elbow pads fit well too, but I have omitted them from my loadout as they definitely do hinder your movement with your ellbows and arms. Maybe I can try to adjust the tightness a bit haven't really tried it out.
Very comfortable and an absolute recommendation. The price on this one is perfect.
Below an image, showing how well they blend with the armor.