I bought a Motorola HS850 Headset to use with my RAZR. I work from my car most of the time and I had been using the Motorola for 3 months but was tired of:

1. The fit on my ear was too loose

2. My clients kept telling me that they could hear an echo and had trouble hearing me

3. Because it is not "in the ear" and it does not fit tightly on the ear, it kept picking up ambient sound in the car (road noise, wind, traffic, etc.)

I thus started shopping for another model that could solve these problems. I first went to Epinions to read up on reviews and tried the following listed below (I have added my rating in brackets for the other models for your info):

1. Jabra BT250v (8.0) - good sound but too bulky and uses a two-piece charger which is not practical when you travel a lot (I have too many different chargers in my luggage already!)

2. Logitech Express (7.0)- at first, I was impressed by the sound loudness and the price but my clients were telling me that they had trouble hearing me and they could hear an electrical whizzing noise

3. Plantronics 320 (5.0) - good fit but not very good sound quality

4. IO-Gear GBE201W7C (1.0) - poorest sound quality ever heard - not even worth the price. If you are on a budget then go with the Logitech instead.

I finally tried the Discovery 640 and I cannot say enough good of it. It has the best sound quality ever. I must admit that using the Motorola was easier as its buttons were more readily accessible, but for size and sound quality, the 640 beats the Moto hands down. Plus, given that I travel a lot, I have bought the mini-USB adapter ($10) for the charging cradle which eliminates the need for another power supply in my luggage as I can just plug it in my laptop.

As for the cons, well, it is so small that I am afraid of losing it and it is true that the buttons are so small that turning it ON or OFF requires attention. (You only have to flip the microphone on the Moto which made it much simpler than holding a small button for 5 seconds, but hey, you can't get small size and large buttons, now, can you?)

Anyway,I have had the 640 for 1 week now and even my mom, who's hard of hearing, could not tell that I was in the car when talking with her. I am thus 100% satisfied with it and recommend it... Goodbye Moto!