Pros: Great sound from such a small driver. Really pumps out some good bass. For 25 bucks it produces some great sound quality.
Cons: While they sound great, they break... a lot. I've had 3 sets break on me. The first one was defective right out of the box- it only output in mono. The second pair the left headphone kind of died and produced a muffled reduced sound. The third pair the right ear went out all together.
Pros: Amazing sound. For such small headphones they have great bass.
Cons: To get that sound, you have to somehow trick them into staying put. The buds, no matter which dampers are used, just don't sit right in the ear, leaving you hearing background noise and losing all the bass. After extended wear (2-3 hours), they are very uncomfortable. The stiff cord makes a lot of noise against clothing and also tends to not allow much motion without losing the buds again. Love the sound, hate the design.
Pros: After switching to a different plug size (where there was a better seal) the sound quality is unbelievable. Great bass for such a tiny ear bud. I actually had to turn the bass down on my mp3 player after switching to these new buds. Not sure about "HD" sound, but its pretty dang good.
Cons: Cord is not very rigid near plug. I've had problems in the past with other headphones wearing out near the plug and the stereo cutting in and out. No problems so far though.