Update, the functions are awesome, just jump in the car switch on the ignition and it pairs so I just have to start the music on my phone.
It can be hidden away as you don't need to press anything if its connected up to a switched power source.
Bad point: Its got a fair bit of background noise when the volume is up and the clarity between highs, lows and mids is not great.
Looks like I will be investing in another more expensive one to see if its got better sound but at £7 its worth a buy!
01/06/2014 UPDATE: Used a cheap AUX noise filter as suggested before and I cannot be happier with the unit, no noise what so ever.
It links straight away and I just use a sticky phone holder on my Satnav screen like blow:
Sound if great and its completely hidden. There are only 2 negatives after using it for over 3 months:
1. The USB charger cable that comes with it is flimsy and I replaced it as it was cutting out, now perfect.
2. If you pop into a shop or move away from the Bluetooth range (which is big) it will not reconnect automatically, you have to manually do it on your phone or flick the switch off and on.
This could be fixed if you removed the battery so it starts up with the ignition but I haven't attempted this as it doesn't really bother me.
Best car audio part for the price I have ever bought!