I use http://www.plantronet.com/productdetails?id=139&categoryid=2
It's quite good in sound quality, but there will be potential problem with holding in ears in summer - in winter it is being held by my cap :)
Yeah, I bought them. The curiosity got the best of me. I"m still undecided. The range thing is definitely an issue. I run with a ppc belt that i used to wear in front. now i have it turned to the kidney so the headset can connect. I love the sound and the fit. I was pleasantly surprised with how well it stays put during a run. However the longest i've been able to keep them working so far has been 1 hour (on a 1.5 hour run...) I love the ability to turn the vol up or down on the headset as well as skip tracks and play/pause. Also, if a call comes in i can press a button on the headset and answer it. The fit is fine for short - medium runs but on my long runs my ear kind of hurts from accommodating the behind the ear swoop. I love having no wires and most of the time they connect fairly easily to my device. So far they are a fun toy for $40. I keep em in the car for phone conversations as well.