Same thing grador said with the Polk ultrafit 3000's. You should be able to pick them up for between 60-80.
The Sennheisers with the ear band are good too. More punchy bass. Not an in-ear-canal headphone, though. Very little customization and poorer build quality than the polks, except at the point the earbud connects to the earband. That's as good or better than the polks. However, the polks have this playdo-like ear band that molds and stuff. pretty cool.
The sennheisers sound good, but do not have the "airy" or "open" sound I usually associate with sennheiser. The polks, on the other hand, do. But again, with very little attention paid to how you have them in your ear, you are going to get much punchier bass.
Comes down to what you really wanna do with them. If it's just for running, I say go with senn, BUT if you're going to the gym, too, get the polks. They are noise isolating.
I also read a review on the polk 2000's. They are the behind the head, on the ear type. They got really good reviews. I think the price on those is more like 50-60.
I also know that motorola has a pair of behind the head, on the ear blue tooth ones that seem to be popular. Doubt they sound that good though. But you're gonna be panting and sweating, anyway.
Hope this helps!
