Bought this 2 years ago when I got a new car which didn't have Bluetooth, but had an Aux.
I paid £40 then and it's definitely £40 well spent. Using it everytime I get in the car as I play music from my phone and have it ready for any calls / read out text.
The only thing is, it doesn't auto sync when you start your car. You need to press the Red Button, which turns Blue when it's connected after the first setup. Not a big deal as it's 1 press and 5 seconds wait, I'm patient enough to do that. Constant pressing when I get in the car for 2 years and the button is still working flawlessly. Now that's good quality.
I use Windows Phone 7.5 and 8.0 to connect, no problem. After connecting, a single press on the button plays music at random. 1 Press to pause, 2 press to skip forward. When I get a call, 1 press to answer, a follow up press to end. My mic is located next to my hand brake, so it's down and not directly infront of my mouth, the recipient don't have any issue with voice quality / level.
Despite that minor flaw, I would happily give it 5 stars, just for what I want out of it and with 2 years daily use, it's still working great. Here's to many more years of service and if it breaks tomorrow, I'll get it again.