I used the Full Metal Jackets for a little while and the sound quality was good. They didn't fit comfortably under my helmet (protrude too far out of my ear) and when using them off the bike the cord transmitted lots of noise through the headphones (when it bounced against my chest or hit anything.
. I use the small ones for $29 there great like I can't feel them under my helmet I use them with my blackberry I rate them a 10 out 10
I used them for a while and they worked great. Still wish they were a bit slimmer profile to get in and out of the helmet easier. I just got a helmet with bluetooth built in so I don't need ear buds anymore.
Sound quality is nowhere near as good as my Shures; but, the Skull Candy's I got are by far the best under a helmet. I picked up the ones that are made to go under a watch cap.
Hey what helmet did you get with bluetooth. I'm considering a purchase this year and can't decide on a kit to modify a helmet or a purchase with bluetooth built in. VManiac16