I've had a bit of knee pain while running for a few weeks and foam rolling wasn't working so I purchased this. I've now run in it 4 or 5 times, including a virtual half-marathon yesterday, and no knee pain. Winner. Also got a new 21.1k PB :-D
Tiny Cons: It is quite thick so it does get a little warm but luckily it doesn't seem to soak up heaps of sweat. On my first run i found it a little itchy but that could've just been because I'm not used to wearing one... itchiness has gone away on subsequent runs. It doesn't slip at all thanks to some rubber/silicon stuff on the lining but it does leave some marks on my skin for a few hours after.