If you actually want good phones, look at the Shure SE115s, or Sennheiser CX 300-IIs. The Shures will sound amazing, but are much more expensive.
I've got a pair of Shure SRH-440 headphones, and they're the best headphones I've ever used. They've got a flat frequency response, isolate all noise at around 40% volume, and don't distort even at 100.
Beats are about like Bose. Horribly overpriced, mediocre sounding name headphones.
And Skullcandy headphones are even worse: horribly overpriced, awful sounding fashion headphones.