I used the Sennheiser PX-100 headphones (very similar in size, price, and style) almost daily for 2 years when one side crapped out. Drat. So I bought the Koss PortaPro's as a replacement.

1. The Koss are not as attractive. Not that important to me.

2. The Koss are not as comfortable. The metal head band is cheesy, when compared to the Sennheiser's, and they are only $10 more. The Koss are also a tad too tight. My ears burned (even when on the loosest setting) after about 2 hours.

3. The BIG problem, and I toyed around with equalizer settings in WinAmp (my MP3 player software of choice), is that the Koss are incredibly easy to overdrive, even at relatively low listening levels. Not so the Sennheiser headphones. Had I noticed distortion with them, I would have chucked them long ago.

Summary: If you want a light pair of on-ear, portable headphones, spend the extra $$ and get the Sennheiser PX-100 (or higher models). The Koss may be adequate for portable MP3 devices where you cannot adjust the EQ settings, but for more ambitious use, they are far too inadequate. I'm buying another pair of the Sennheiser's.
I used the Sennheiser PX-100 headphones (very similar in size, price, and style) almost daily for 2 years when one side crapped out. Drat. So I bought the Koss PortaPro's as a replacement. 1. The Koss are not as attractive. Not that important to me. 2. The Koss are not as comfortable. The metal head band is cheesy, when compared to the Sennheiser's, and they are only $10 more. The Koss are also a tad too tight. My ears burned (even when on the loosest setting) after about 2 hours. 3. The BIG problem, and I toyed around with equalizer settings in WinAmp (my MP3 player software of choice), is that the Koss are incredibly easy to overdrive, even at relatively low listening levels. Not so the Sennheiser headphones. Had I noticed distortion with them, I would have chucked them long ago. Summary: If you want a light pair of on-ear, portable headphones, spend the extra $$ and get the Sennheiser PX-100 (or higher models). The Koss may be adequate for portable MP3 devices where you cannot adjust the EQ settings, but for more ambitious use, they are far too inadequate. I'm buying another pair of the Sennheiser's.