I'm trying to be realistic here.
I'd want a car that I know I could easily afford to fix, one that wouldn't cost appreciably more than my EP3 does to run which pretty much rules out any of the beemers there.
My shortlist:
Happy feel good car - Audi 100S. On a hot summer day with the windows down this would be hard to beat. However, no aircon, crap heaters and lack of any creature comforts would rule this out.
Realistic sensible car - Opel Monza. Probably the cheapest to keep in a good state of health out of these 4, but it's a bit of a munter and has no aircon.
Slightly nearer the wrong end of the scale - Merc 190 Cosworth. Now you're talking. All the bells and whistles I'd want, and not a ridiculous V12. Good performance, and not too bad for my ~10-12k per year. Not too bad to maintain?
Possible at a push - BMW 635 CSI in Royal Blue. Probably my favourite car out of the 4. Fuel costs might kill me, as may general running costs associated with maintenance.
So I'd probably happily end up with the 190. If running costs were no object, then the E34 M5 for sure.