External GPS microphone recommendation?

[mvalpreda]

I am looking for a decent microphone to use with my Garmin C550. I find that where I have the unit mounted is a bit too far away and when I'm on the phone people don't like all the background noise or me sounding like I'm in a tunnel.

I'm not overly concerned about price, just something that has some decent noise reduction in it.

Anyone used anything like that?

Thanks!