I think it's over-simplistic to say "well, you're smart to have a depreciated classic car, so of course you should repair it rather than allow yourself to own something that depreciates." At 210k miles without these repairs having been done, he has a car that is worth maybe $1500-2000 on craigslist. The original poster is potentially looking at:

- pads and rotors and sensors ($1200?)
- timing chain and rails and tensioners (cost me over $2500 on my 500E 4 years ago)
- wiring harness ($1500? - I'm guessing on these costs, so please forgive me if I'm way off)
- evaporator ($1500? $2000?)
- transmission ($3000+?)

These could all come in rapid succession. So if all of it happens in the next 24 months, you're looking at maybe $8000-10000 to keep a $2000 car running. I spent something like $7500 in a 12 month period on my 500E on things like this. And the fact that I had a car that wasn't depreciating like a new car did not make me feel one bit better.

I loved my 500E (got rid of it 3 years ago) and last month, I was in the market to get another 4 door sedan. I thought really hard about a 400E/E420 and the 300E/E320. Between head gaskets, wiring harnesses, timing chain rails, AC evaporators, etc., I just couldn't do it even though I could buy a nice example for $5000. I ended up picking up a 1999 C280 in very nice shape for a little under $9000 because it doesn't have all of those known high ticket failures. I'm sure I'll learn over the next few years where this car is weak.

If it were me, since the original poster's car runs great and there are no signs of imminent doom otherwise, I would do the brakes and keep driving it. But be ready to bail when the grim reaper comes.