F80/F82 are absolutely fun cars to drive, also can be scary too (and loud as hell lol).
I test drove my uncle's F82 M4 two days ago and I love it. I have only drive 2 european cars so far (a Toyota owner for life here) and both of them are his, the 2010 SL350 and the M4. I don't know why the SL350 throttle pedal is heavy as hell while the M4 feels so good and responsive.
Yeah the M3/4 F8X and the Audi (RS4/5) /Merc (AMG C63) equivalents each have their stronger points. All incredible cars, and I suspect most would be happy any of them, particularly if moving from non performance cars.
Audi's 4WD drive stick to the road in all but extreme conditions, more idiot proof in terms of floor it with little care for losing control unless being a total lunatic on the road. Down side is not quite as agile or 'alive' as M cars imo due to 4wd, extra weight- but like I say, certainly not dull by a long stretch.
AMG C63, sounds best of the 3, incredible v8, rwd, but again, heavier than M3 so brings downsides.
BMW probably not quite as good sounding compared to other 2 (but i like the straight 6 sound), but this class is BMW's bread and butter and they seem to have weight distribution, handling down to a tee... more agile than the other 2. RWD, like you say, great fun, been taking around B rounds in Dorset this summer and its great fun. 60mph to 100ish is something crazy like 3 seconds... some m3 purists don;t like the turbos, but torque is always there from the 3tlr twin turbos.... I've never used full auto, always the paddles... Novelty/fun hasn;t worn off in nearly 18 months ownership... trips to shops can turn into 2 hour detours, love the way it looks - good balance of aggression/classiness imo

. I love the damn thing, no regrets at all, after dithering about buying a performance car for years. I have the Competition version, so 450BHP, no chrome and 666 20" alloys.