I have used many many products on my bike to protect it and make it shine, some very expensive and some cheaper but the best by far is believe it or not "Tesco's own brand bumper & tyre restorer" - just make sure you don't get it anywhere near your brakes (as it says on the can)
All I can say is that my bike is gleaming, clean and rainwater & traffic crud sheds off it so easily.
A lot of the specific cleaners seem to have an inherent static problem which attracts dust and road crud.
It's really cheap too!
