Not long after I bought my 2 I found out that the previous owner had had the car treated with Diamondbrite.
Now I'm a bit sceptical when it comes to these treatment systems, but I thought "what the hell" and bought the Diamondbrite shampoo and conserver kit (cheap off ebay). I gave the car a good wash this afternoon, followed by a hosing down. After drying the car I applied the conserver as directed and hosed the car down again - finishing off with a chamois leather. I must admit I was extremely impressed with the way the water beaded as I hosed off the conserver solution.
On a previous occasion (before I bought the Diamondbrite kit) I'd used my usual car wash soap and was amazed at how easy it was to wash the bugs off the front of the car. Maybe there's something to this sealant system after all!
There's a video and some information about the system here:
http://www.clean-image.co.uk/paintsealant/diamondbrite.htmI'll update this thread from time to time to let you all know how I get on with it.