By the way, I bit the bullet and went with the Shure E3C headphones for my iPod. Dang! These things are amazing. I an sitting by the window of the plane and when I turn my head I see the engine right behind me (Seat 27A on a Boeing 717 for those keeping track). I can hear nothing *NOTHING* but the music.
On the Metro last night, I could not even hear the train. Absolutely amazing. But I cringe at how much I paid. I was going to go with the Etymotic 6i, which was $20.00 less, but several people in the Clarendon Apple store said they preferred the E3C’s a bit better because they really bring out the middle level of the music and, more importantly, the wires are thicker so you are less likely to hear through the earbud when your shirt brushes against the wire — something you have to think about with in-ear buds.
Also, with the Etymotics, I read a couple of reviews of people who got them stuck in their ears. They were yanking them out and the wire snapped off. But, I think perhaps the biggest difference was that even though the Shures were more expensive up front, every review said that the long term upkeep was less because of the filters used by the Etymotics.
One last thing, now that I’ve landed. Just how quiet is the Shure E3C? The stewardess had to come by and tap me on the shoulder and tell me to turn everything off because I could not hear the intercom in the plane. Even then, she started talking to me before I got the earbud out. I saw her lips moving, but I heard nothing. Amazing!