I use the HS810 and like it a lot, but as CT-UK and others said, it's not that useful in the car because of the low volume. I also have that trouble with it sometimes when walking through airports: I find myself pushing it against my ear to hear better, which obviously defeats the purpose of a hands-free headset.

I'm thinking about a car kit and wonder if anyone has any experience with either the one (Motorola's, that is) that requires professional installation and is mounted on the dashboard, versus the portable wireless speaker (HF800), which I think just clips to the visor. If I go the cheaper route and get the HF800, will I be frustrated by the same low volume problem that I have using the HS810 in the car?

And is the new headset, the HS850 better for use in the car than the HS810, or pretty much the same?