I had a Jabra BT250v but never was satisfied with its fitting (always dangled and felt loose) - poor reception and weak volume (always had to press the earpiece against ear canal during phone conversation)!
Recently, after reading all the positive reviews about this headset on Amazon, with the price, I went ahead and gave it a try!
Within the first few hours, this gem just blew me away. To make it less wordy, I would list the characteristics that make this an excellent product -
1- Easy to mount onto ear with one hand (hold at the base of the earpiece and the mouthpiece, press the earplug into ear canal then use index, slide finger top under the gooseneck of contraption to guide the wraparound piece to fit behind ear)
2- Tone to let user know that connection to phone is established
3- Tone for volume adjusment (no need to have a call to adjust volume)
4- Very loud and audible
5- Excellent reception
6- Good battery's life
7- Good looker
One caveat though, it's easier to turn on before mounting since power button was small and needs to be pushed to the left (with microphone boom points downward and away from user) then pressed down to activate

The Plantronics Voyager 510 is a great choice for bluetooth headsets. Audio is really clear for both speaker and listener. The headset is very durable.It even holds a battery charge for several days at a time.I will
purchase again,it is highly recommended!

Definitely a solid bluetooth headset for the price. Fits comfortably around the ear and the ear piece isn't an issue. For some reason unknown to me, it worked great while driving but not so much around the house. I wanted to use it hands free while at home but sound quality wasn't up to par with what I expected. Also, the individual on the receiving end would always complain that I sound like I'm talking several feet away from the phone. However, this issue wasn't a problem while I was in my car where sound quality and voice quality were excellent. I would definitely recommend this for anyone that needs a cheap headset for use while driving. For those that need a headset for their office exclusively, I wouldn't suggest this headset.

Plantronics Voyager 510 Bluetooth Headset with Multipoint Technology

Purchased this product before as a gift; however, due to damage, product needed to be replaced. Request was to obtain same bluetooth headset as user liked all the features and did not wish to get any other. A great buy! Have also purchased other bluetooth headsets from Plantronics and have not been disappointed. Would recommend to others.

Other than the common complaint of the power button being too small, this thing is awesome. Great sound (yes even outside in the wind) and the people on the other end say I sound great, maybe even a little louder than normal. I wanted a jawbone but couldn't afford it (thank God). My friend that bought a jawbone is actually jealous of my 510. It also fits great on my ear and it's almost impossible for it to fall off. All in all, love it, well worth the money.