I think that spot creams are a load of rubbish, from experience. They help, if at all, the result of acne, but it doesn't really prevent spots. I know they come out with this scientific evidence, but if it was really that simple and easy to treat, then why do people still get spots when using the products?
I think the best thing you can do is drink lots of water, do regular exercise, eat healthily, be sensitive to any foods which worsen your skin, and get some sun on your skin. I don't think that sunbeds are a great idea though, they're preeetty bad for you from what I've heard.