Having put plenty on miles on both chassis, I'll say there's not a huge difference in ride quality, comfort, interior, etc. between the two. That said, the w211 being newer, it'll be easier to find one in nice shape where the interior isn't trashed. There are lots of beat up abused w210s out there unfortunately.

In terms of the electronic features, the early w210's don't have much, but the later w210's do. I'm talking about things like the rain sensing wipers, the tilting right side mirror, automatic starter, hill-hold, ASR-disable switch, etc. I think all w210's had the Homelink garage door opener as standard, as do the w211's.

The w210 is easier to work on and perform maintenance and repairs. The w210 will require a diagnostic tool with proper 38 pin MB interface. Cheapest one I know of that supports ALL the w210's computers and works really well is the Autel MD802 + Autel Benz-38 adapter, total of around $300. The w211 can do everything via the OBD2 port.

The w210s are old enough now that you have to think about replacing all the rubber suspension bits like control arm bushings, rear carrier bushings, shock absorbers, etc. Where I think most used w211's will still feel decent as-is for a few years.

All used cars will come with some amount of "deferred maintenance" that the new owner will be saddled with. Depends more on the age, mileage, and condition of the vehicle, than on which body generation it is.

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1998 E300 turbodiesel

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