I managed to do 600 miles a few months ago in my 210,000 mile 1.8 MK3. I had to go up to london from cornwall, planned to stay over night but i was up for the drive and it saved money so we did it in one go... Didnt let me down once! I have alot of faith in my old girl though, I never see it as a reliable car but after 210k miles the engine stick ticks over almost silently, not even the slightly faint tapping or ticking from the valve gear or anything and i usualy rack up over 1000 miles per month... Bullet proof or what?