I couldn't get stereo from my cell phone because of the way it's wired.
I could use my hands free ear bud and get stereo but the audio was so low.
I spend $39.00 for 1 gb SanDsk MP3 player and it worked great.
I bought a stereo headphone set and took the "over the head" piece off.
The speaker part fit in my HJC helmet great. $20 for headphone at Wal Mart.
I tried using my T-mobile Dash (HTC) over the weekend. It came with a set of stereo headphones/mic kit. I was not extremely pleased, but I do not think it was the phone's fault. The wind and vance & hines I figured were to blame on not really being able to hear very well. I've actually been looking around the web for some other options, but do not want to pay 3-400 bucks for a kit. I have an iPod and other brand Mp3, but do not want to carry it and the cell phone... Oh well, I'll keep looking.