One of the problems with the Zumo550 is that the bluetooth is only mono.
This company has put out an adapter that plugs into the cradle, bypasses the built in bluetooth, and puts out stereo bluetooth.
You can get the transmitter with or without the headset, in case you have
a stereo bluetooth headset already.

http://www.collett.mb.ca/

Being a bit of a minimalist I'm sometimes surprised at what we in this consumer culture regard as problems.

The bluetooth in the Garmin Zumo 550 is just mono? My understanding is that the detainees at GITMO often taunt the US guards with that fact.

Okay I've removed my tongue from my cheek now.

The adapter does look pretty neat and is probably really usefull.

You must be one o dem guys whut had to walk 10 miles to school, uphill, both ways, in the snow. And you held yer little brother upside down in front of you to breathe hot air on yer
legs cause you couldn't affort nuttin but shorts.
And yer sister wore tight little dresses cause mom didnt want
to waste material, so she cut some of it off to make sleeves
fer yer undershirts.
Remind me to stay off yer lawn. LOL

Not really an accurate portrayal of my youth growing up in MN, other than the reference to snow. There was snow. Although we did grow up without a lot of money, we were sort of unaware of what we were missing out on. Except for the lack of indoor plumbing. You cannot overlook that little bit of reality in January (in MN) as you contemplate a walk to the outhouse.

If not for the neighborhood association I'd let my lawn grow wild. So I guess I'm not too concerned with who walks on the blasted stuff.

The Scala Rider Q2 headsets we use for bike to bike communication are mono bluetooth. Not really the end of the world as I know it.