I've had my mk5 GTi for 3.5 years now (it's 4 years old). I normally only keep cars for 2 to 3 years and the golf is now the car I've owned the longest, which has surprised me.
I'm planning to keep it for another 18 months so it'll be 6 years old and I would guess milage will be 75k to 80k miles but may well keeping for longer.