I've always used canalphones, but recently, I've wanted to try some headphones instead. My 2 top contenders are the K81DJ and the ATH-FC7. I'll mostly be using these headphones for walking to work, on trains, etc. I want headphones that are fairly portable, comfortable, decent noise isolation, and above all, good sound quality. I can get the K81DJ for about $60 and the ATH-FC7 for about $30 (both from a friend). Which of these 2 would you recommend more?