I attribute my exhaust rusting off at 75K to too many short journeys. Moisture etc. Generally though, short journeys around town are bad. Lots of tight bends, lots of pot holes, lots of cold running, lots of gear changes. It just knackers cars. I reckon 50% of my driving is short town trips. The car is feeling a bit tired at the moment. A few rattles, knocks and I think a wheel bearing's on the way out too. If I did more motorway cruising, I doubt I'd have had some of the issues I've had .