At first I bought one pair.  I was really looking for something that would stay dry, not bunch up or hinder working out, and would still be comfortable without being too tight.  After wearing these for a while, I went and bought two more pairs.  I love them.  They are long enough to be below my knees, they are tight, but not so tight that I feel exposed while wearing them.  The best part is that when I sweat they stay dry.  Highly recommend!