Cool
. I've been using bluetooth headsets for the last 4-5 years and it's great on longer trips. I bought a set of Scala rider Q2 for $200 (one for me, one for the girl) and it was especially useful during our coast to coast trip.
It can hook up to 3 bluetooth devices (phone, GPS, MP3). The intercom feature is very useful because I didn't realize my girl's AT&T service suck so bad due to dead zones until that cross country trip. The intercom runs on radio wave so no cell phone signal, no problem.
The G4 is the newest version but the Q2 is still running strong.