PROS: Fantastic sound quality -- music reproduction is pure without any loss of fidelity or unnatural boosting of frequencies at either the low, middle or high end; comfortable for listening hour after hour; 1/4 stereo connector unscrews to reveal a 3.5mm stereo connector. CONS: High rated impedance of 120 ohms -- will not get loud when plugged into the average mp3 player; headphone amplifier is recommended for PMP use. These aren't as good as the legendary K240s, but the price was less than half of the price of the K240s, too.