If your budget allows (as this is NOT cheap) try Shine-On detail (
Professional Car Detailing : Shine On Auto Detailing).
The guy's name is Paul and he actually featured on 5th Gear earlier this year when they did a feature on car detailing. He predominantly uses Swissvax products which is why he's not the cheapest...but the results are outstanding. Your cars' paintwork will look better than when it left the factory...seriously!
I had my previous e92 M3 machine polished by him and my M6 is being done next week - it's covered with some very noticeable swirls which Paul simply makes disappear. Check out the examples on his website...I will also try and post some before and after pictures on here when he's done mine.
He's based in the Reading area but will come to you - I live in Leicestershire which isn't exactly local for him but his travel charges are reasonable and definitely worth it.
Highly recommended - I hope this helps.