Thank you everyone for the input! Very helpful. I decided I would wait a little while and buy the Stennheiser Momentums because I agree that it's probably better to spend a little extra on something that seems perfect. I have fairly small ears, too, so I'm not worried about the fit.   Thanks...

I've only ever used ear buds, but either my ear canals are weirdly small or I'm just over-sensitive but I find them incredibly uncomfortable and they never stay in. I'm looking for a portable pair of headphones to use to listen to music on my ipod and cellphone while I'm walking around outside...

Also, like I said, I'd like them for when I'm out and about so noise cancellation for noisy traffic and stuff would be a bonus.

I've only ever used ear buds, but either my ear canals are weirdly small or I'm just over-sensitive but I find them incredibly uncomfortable and they never stay in. I'm looking for a portable pair of headphones to use to listen to music on my ipod and cellphone while I'm walking around outside...