[davidsh]

Well, the etymotic hf5 has possibly got the best isolation you can get and also superb sound quality. On the other hand, they are not that comfortable, and not everybody like their sound signature. Also, they are good with most genres, but excel at classical music, since they are very neutral sounding.
IMO they can stand up against many fullsize cans, but their soundstage ofc is not as good, and they dont extend as much in the highs and lows compared to the 300+ cans.