Both my best and worst car was a 1998 Volkswagen Passat I bought in 2001. It was loaded; every option, including leather and a fairly powerful v6 engine. It was one of those cars that handled high speed so effortlessly, it surprised you when looking at the speedometer; "Oh shit I'm doing 95!" The interior materials were uniformly high quality. Excellent fit and finish throughout.
What was wrong with it? Everything else. Every month or two, the car would suffer some issue that required no less than $800 to $1000 of work. Not struts or something that could be fixed anywhere, but specialized things that could only be repaired at the dealer or a high-end mechanic that specialized in European cars. The engine was on the verge of seizing up at 90,000 miles due to oil sludge resulting from a faulty oil pump, and I traded it in on a Subaru Forester. I told the dealer abut the engine, and they didn't care; they just sent it off to auction,
What was the worst car you've ever owned?