Best - 1978 Chevy Camaro. Why? Highway Star by Deep Purple played wherever I went.
Worst - Austin Marina. Why? British Leyland...hello?
First car was a 66 Opel Kadett wagon. Bought it for $260 and had some great memories in the back of that car. The 69 Camaro SS convertible, 396 was a beast and the girls liked it but was truly a bucket of bolts. Put 200K on a 1980 Benz CD that never stranded me. Worst was probably my 2001 Chrysler LHS. Needed a new engine at 90K.
Ha! I had a '74 MGB. Good thing I'm a shade tree mechanic. It was constantly having problems. But when you have the carbs synchronised and tuned up, it was a blast to drive! Especially on Highway 90 down the beaches of the MS Gulf Coast in Summer. Would get scratch in 3 gears...