depends which model you're talking about. I've got a pair of the skullcrushers (the one's with the built-in subwoofer) and I love them, haven't had any problems with them whatsoever. Can't take those on the mountain though, one fall and they'd go flying, pretty bulky.
Skullcandy is the best stuff to jam in your ears. The sound quality in all of their products is unbeatable for the price. As far as durability goes, I haven't had a problem with any Skullcandy product, ever. Besides, they have a lifetime warranty that basically says you can break them however you want, and they will replace them.
I absolutely hate skullcandy headphones. They break really easily. I had two pairs of the ear buds both broke within two weeks. Also, listening to music threw them while snowboarding? For get about it. They slip off easily.