After giving this a great deal of thought I ended up deciding to go down the professional detailer route. I was scared I might make a complete mess of things and I wanted to be 100% confident that the car was getting the best treatment possible.
So I contacted a detailer which another forum member had suggested and got a couple of quotes from him for two different treatments. The first quote was for a polymer based sealant which I was told would protect the car for about 6 months. The second was more expensive using a ceramic sealant but had been tested up to 18months.
I decided to go for the more expensive treatment as I thought that I had spent £28k + so far so what was another few hundred for peace of mind.
I handed the car over to Richard last Wednesday and it took two days to go through the entire process which was:
Wash using two bucket method
Remove any remaining residue on car
Correct any defects through machine polish
Clay the car removing any contaminants from transportation
Use sealant on paintwork and wheels
Apply further layer of polish for protection
I have to say Richard did a fantastic job and the car was sparkling when I collected it

Anyway here is a link to Richard's page to see pics of the full process
https://www.facebook.com/media/set/?set=a.206724579491641.1073741848.137800909717342&type=1And here are a few pics of earlier this week showing the beading on the car after some rain


