i use auto glym ultra deep shine on my s2 and it brings it up nice. you only need a little bit as it goes quite a long way and if you use too much it's a bitch to get off. make sure you don't just polish though as it won't protect the paint. use something like auto glym extra gloss protection followed by a carnuba wax of some kind as this will provide a good layer of protection as well as giving a nice deep shine to the paint work. hth
tom