I say the T9, since you're in a hurry to decide, it has a lot of features, it would be easier to operate than the great-looking K3, and because the sound should be very good. (You might want to pay a little extra for a replacement plan/warranty with just about any player at any price range ... I didn't with the inexpensive Stone, which sounds good by the way, but why not go right to the T9 in your situation?).
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Phones (in order of purchase):
Sony MDR71, Sony MDR51, Etymotic ER6, Panasonic RP-HJ50, Shure E3C, Koss PortaPro 2, Creative EP630, Etymotic ER6i, Sennheiser PX-100, Sennheiser HD555,
Sources (in order of purchase):
2nd Generation 10GB iPod for Windows (retired)
Creative Muvo 256MB
Creative Muvo 1GB (out on loan)
Rio Carbon 5GB
Cowon iAudio 5 1GB (out on loan)
Rio Karma 20GB (low-mileage collector’s item)
Creative Zen Nano 1GB
Samsung YP-U2 512MB
4th Generation 40GB iPod (monochrome; used as home jukebox)
2nd Generation iPod Nano 4GB
Creative Zen Stone 1GB
iRiver T60 2GB