I use the Showroom Shine by Grease Lightning, but I know there are other similar products on the market. I'm in to my 3rd bottle of the stuff and believe me, if it damaged the paintwork, I would not use it. There is not a mark to be seen and my car is Mica Black, so it would show.
For the best results you will need the recommended micro fibre cloths.
I found the best place to buy it was Ideal World. When I bought my second lot, as with the first lot I bought, they were selling two 1 litre bottles for the price of one.