None of them have been bad, as I buy Japanese cars. I had a BMW E46 for a year and it was not very well made, although it went pretty well.
Best for its age was a Mk1 MX-5, which I would happily drive to the ends of the earth even when it was 15 years old and had an impressive mileage. They don't like road salt, though, and rot at the sills.
Worst was a Toyota Yaris T Sport - flimsy and didn't start one day (2 years old at the time). And I had a Suzuki Jimny with a bad clutch release bearing at 21,000 miles. Probably dry from new, as I don't ride the clutch and rarely drive in towns. New clutch job at a fixed price from the main dealer - you don't take the gearbox off and not do the whole lot, since the parts are only about 25% of the total.