Of course I'm (happily)biased but for a bit more money why not go for the 500E/E500? They are pretty reasonable to pick up now and will might be worth something more down the road. Not that a nice 400E/E420 wouldn't be either...but the 500E is destined to become a collectors item.
First off, they ain't cheap to maintain, especially at this age. Shame on anyone who says differently. Mileage is a moot point IMO but regardless of it, LOTSA stuff will need to be attended to and will certainly tax yer wallet and patience. I know cars with 50K on them needing $$ and my 144K car also needed continued $$ to get it and keep it right. Really, what 10+ year old car doesn't? But the M119 is a great motor when happy and in my car I get as low as 12 mpg hammering it around town up to 22 mpg cruising the highway at 80 mph. The chassis speaks for itself...solid in any version. We knows this already...
I don't think you could go wrong with any W124 with the V8 in it. Just have a few grand set aside for 'incidentals' ...is all I'm really saying.
