My 240D has the collapsed/shredded seat. I was expecting to experience some back pain when I drove it all the way to LA and back, but luckily it didn't happen. The seat on my 300D is in good shape and I drove it to Atlanta and back without pain. I think it helps that I have the seat back adjusted as close to vertical as it will go.

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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.