My top three:
1. V Three BTH8.
Love the full OLED display, shows every bit of info, including Caller ID, battery life, and connection status. Has memory of incoming calls which I can scroll through and dial directly from the phone.
The biggest negative is the built in microphone, it is not the best of quality.
2. Tekkeon ET3000.
The US version of the BTH8 (I imported the BTH8). But it has some quirks that make it inferior to the nearly identical BTH8. For one Tekkeon in their infinite wisdom decided not to include an internal battery, only a ginormous battery ear loop (with the BTH8 I can use both if I want).
Also, the Tekkeon's caller ID scrolls, even though all the numbers are displayed, very annoying, the BTH8 does not do this.
Built in Mic sucks too. I modded it by swapping out the Microphone with an ETY-COM boom mic. Worked awesome until the Tekkeon just stopped working one day. Hence why I bought the BTH8.
3. Sony Ericcson HBH-662.
Longest range of any BT headset I've ever used, and the outgoing sound is still clear even if it is staticy and breaking up on my end when I've reached the outer limits of it's range (a bit more than 10 meters, even through walls!).
Downside is the Caller ID window is tiny, and cannot display all 10 digits of a phone number at once, so it scrolls it. And the battery meter is really inaccurate. Also the speaker part does not get very loud.
If you noticed I really like having a BT headset with Caller ID displays, probably because I have a PDA phone that is a large brick.
-Ed