Porsche 911. There's nothing wrong with the older ones all the way back to 1964, but of the ones I've driven, I like the 911 SC best, and those were made from '78 to '83.

I had a '77 240D as a daily driver from '06-'10 until I used it as the tranny donor for my 300D. If one could be had in new condition, I don't think I would have any problems using a '68 200D as a daily. A fintail would most likely be fine as well, but the oddball vertical speedometer turns me off. About four years ago I worked with a guy who used a '59 Ford Galaxy as his daily driver.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 401,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 26,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
99 Mazda Miata 183,xxx miles.