Simple decision. How much of your own work do you do, and do you have a good source for used parts?

W210 - simpler car of the two. No hydraulics, gadgets, toys, etc. Not as nice a ride as a W140 but much cheaper to keep on the road. Can be taken to a mechanic once in a while without emptying your wallet.

W140 - amazing car, but complex. These cars were $100,000USD when new, and parts prices and repair frequency is still based on that. If you take it to a mechanic and start fixing stuff, it will get expensive FAST. But it's not a huge amount harder to work on than a W210

So if you do all your own work, W140. If you rely on dealers, mechanics and have limited sources for cheap parts, W210.

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