Etymotic Research HF5 Portable (Cobalt)

Pros: Crystal clear sound quality
Great accuracy
Excellent noise isolation
Do not fall out of ears
Love the color
Little to no cable noise
Three different eartip choices
Most accurate in price range

Cons: A little on the pricey side, but you get what you pay for.

Summary: I see a lot of complaints about the bass on these earphones, and obviously those writers don't know what they are talking about. If you know how to wear these earphones and get a good seal, the bass is defined, but not overblown (like in the beats headphones by monster)
Besides, you can always throw on the bass booster in your EQ if you care so much about it. The highs are unbelievable, so crisp, clear and 'eargasmic' as I call it.
The noise isolation is excellent on these, almost too good... I can't hear much of what's around me, but it enables me to get the same dynamics out of my music without the increased volume. It's great for travel especially.
There's an app on the iPod/iPhone for the hf3 versions which uses the mic to pickup on sounds you wish to hear (i.e. ignores background noise but will let through things that are louder like important noises (train stops))
I would recommend this to anyone who wants a good earphone, and knows a thing or two about audiology