My Mk3 valver is a daily, does nearly 80 miles a day on workdays, lives on the drive (garage is taken up by the camper), gets used to take garden rubbish to the tip, and gets cleaned ... occasionally.
On the other hand, I bought it a year ago with 101k on the clock, it's now got 124k and has barely missed a beat, the one time it hit trouble was only a split vac hose and it still got me home (a bit jerkily). Apart from a decent exhaust I've hardly done anything to it bar a bit of rust treatment, and it still knocked out over 153bhp on R-Tech's rolling road.
The missus was so impressed she bought a Mk3 8v to replace her Fiesta when it died last winter. After a good service that one hasn't had any issues either.