I took davidfsmith's advice and went to Sexton's in Wandsworth and had a Parott Ck3100 kit fitted. I was very pleased with the service and the fact the dash is completely unmarked from the install.
The Parott kit sounds good and people tell me that the quality is good their end. I took the advice from one of the threads on here that said not to have the mic by the A post airbag, so I had fixed in the centre by the map lights, which is also handy if the passenger wants to talk.
I'm not 100% sold on the position, but theres nowhere else to put it, apart from sightly higher, just have to see how my passengers find it and if they think its in the way getting in and out.