Great ear phones - sound is really crisp and clear, while the bass these kick out is unreal. That is of course, assuming that you've got them properly fitted.
The mid-sized ear buds work fine for me, blocks out most (not all) external noises as well so good if you want to escape some distractions, or just enjoy your music.
There's a little bit of "noise" from the cable moving, but this is to be expected on any proper in-ear head phones like these.
As mentioned by another reviewer however, the headphone cable isn't as pictured - it's just standard black coated cable - which is a little disappointing.
Overall, great headphones that seem pretty sturdy (only been 3 days though, so fingers crossed), but a shame that it's not as pictured with the more flexible/secure looking cable.