Cons:Only works half the time, very weighty, needs to to turn off and on
Yes, they do sound really good for rather cheap headphones... when they work, that is. The minijack -- the part that actually connects to your MP3 player -- is very shoddily made, and doesn't connect well. This makes things sound as though they were coming through an overworked amplifier from several hundred feet off.
The cable is very stiff, and doesn't like to change its shape. This means that when your standing up, the wire just arcs off into space, ready to get caught on anything it can find -- door handles, corners, whatever.
Worst of all, the headphones actually need batteries, and it needs to be turned on and off if you want the "advanced dynamic noise cancellation technology" the packaging advertises. So, consequently, you have the weight of two AAAs hanging from you in this lump in the middle of the cable. You can get around the weird feeling this puts on your ears by putting it in a pocket, but now that's one pocket you can't really put anything else into.