I left mine till 80k (not ideal !!), as others have said you can never get it changed too early. It's peace of mind. Just make sure while they've got it all apart for the cam belt that they fit a new water pump too because if the water pump ever goes it's a pain to get at and they may as well do it while they are doing the cam belt.

I was advised to ask for the water pump with the metal lugs, not the plastic ones. They supposedly last longer !

Mine cost about £250 for cam belt and water pump, so do shop around. My SEAT dealer quoted over £400, but my local VAG garage did it for much less.

Regards,
Andy