I use Autoglym
I took delivery of my F10 on 7th January and at it's first wash I could feel how "dry" the paint was, not very impressive for a brand new car
Less than a week later I gave it the full clay, polish, hi-definition wax treatment and now it feels as fresh as my old E60, much happier. Washing is now a nice uncomplicated procedure because the paint has better protection and doesn't want to hang on to the dirt.
Also I use totally Autoglym products, you can get a hang up about the best wax for this, best polish for that but what's most important is that you actually get out and do it!