Does anyone have any feedback on which model is more reliable? Thanks.

 

Each has its own issues.The w211 just costs more and is more complicated to work on when one of those issues pops up.
W210 is easier to diy,parts are not that pricey,and there is a vast network of diy help built up.
inspect,inspect,inspect.
ohlord

 

Stick with a W210 2001-02 car. W211 as ohlord says are too problematic and expensive to fix. Or, as we all, wait, with a lot of hope, for a W212. And I have to say, W211 are beautyful cars to owns ... when they run.