These new cans just keep getting better every day. Finally, after some 90 hours of break-in these phones are providing timbral accuracy, instrument separation, deep tight bass, amazing mids, and clear highs.
They are expensive at $700 but what a great investment. I'm getting excellent sound just from my 5G 30 gig iPod.
The balance is a bit better than the RS-2i I had for two weeks but that is also a great deal at $200 less, especially if you don't need the extension cord that comes with it.
The RS-1i does sound a bit nicer with a headphone amp but they sound damn good with an iPod. They even sound good on my iPhone 4 with EQu app.