I was riding yesterday & crossing a man-made river bed that was a little slimy I guess. The bike slid out when I hit power band & ate it on my left knee, & nothing else. Well my knee is swollen as a mother & I'm hoping it's not a fractured kneecap. So this puts into perspective for me, maybe I should get some riding protection gear. In everyone's opinion, what are some good knee guards that aren't really expensive (broke college kid problems). & what are some problems you have with wearing them. Pros & Cons. Thanks!