IMO you're going to get tired of loading and re-loading the MP3 player.... also, two hours of music when your moods are changeable may equate into not wanting to listen to anything you happen to have on the player! If you don't mind something larger, the iPod is the best you can get, ESPECIALLY if you're going to use the Etymotics. I have the ER-4Ps and while they sound incredible they're very very very revealing of source limitations... the iPod is the only MP3 player I've ever heard that A.) has enough power to drive the Etys and B.) sounds good enough to listen to through them. There's also the side benefit that you can throw a good chunk of your music collection onto it and carry it all at once. I even throw audio books on mine for those LOOOONG trans-pacific flights.