I have a mk5 Volkswagen Golf GT TDI, which before and during my ownership I have maintained and serviced on a yearly basis. It is currently on 120,000 miles and the cambelt was last changed at 57,000 miles by Volkswagen. Is it OK to drive it for a further 10,000 as quoted by my local garage? Or is it better to change the cambelt and water pump now, even though in the service book it says OK up to 80,000 miles?