Pros: Comfortable, smooth
Cons: None, really...they're not wireless...
These headphones make you forget you are listening to headphones. They are so comfortable, so natural sounding, they are a joy. They have enough oomph to rock out (I don't think they are the ultimate electro/synth/rap cans) and yet present the most delicate classical music.
After about 12 years of CONSTANT use they finally gave up the ghost. Sent them back to Sennheiser for repair and was told they were beyond worn out. Got 50% off for a new pair of HD600s.
I cannot think of any piece of audio or video equipment that gave me more pleasure for the money than my HD580s. Best bang for the buck I ever had.