Klipsch S4 easily, assuming your store carries them. Pretty decent sound, far better than the shitty Bose earbuds. Shure SE-115 is also a decent set, but they made me feel like I had cotton balls in my ears. The S4 set is pretty comfy IMO. The most common complaint I've read about the S4s is sizzly highs, but my Sansa Clip+ has a nice 5-band EQ to help tame some of the problem frequencies. They have a pretty full sound, with enough bass for most peeps. I don't think I found the midrange to be offensive, so that's good for my music (rock, metal, etc.) I slightly prefer my Denon AH-C551K set, but that's only because I find the amount of bass more satisfying. Not quite as comfy as the S4 set was, though.
The S4 set has a 2-year warranty and if you don't like them you have 30 days to return them to BB.