My PX100-ii's just failed after 3 1/2 years of use... and I immediately repurchased. I am a professional musician and own much more expensive headphones and headphone amps for mixing and critical listening, but these are what I use on a daily basis for exercise, work, and travel.  These paired with a Sansa Clip are the perfect exercise rig!  The accentuated upper-bass/low-mids might not be to everyone's liking, but for exercise and travel I prefer this sonic signature. I love that with the PX100-ii's I can hear my surroundings.  I tend listen at low...