TBH, when I first ordered my car, had the M4 been available, I'd have gone for the M4.
Now...I'm not so sure.
The M4 is a great car - no arguing there.
But for me, the problem is that having the M4 as a DD would just seem as a wasted potential.
I think my average commute speed is somewhere around 40-50kph (25-30 mph).
I don't even have that many places where I would be able to legally use launch control to go from 0-100kph (62mph)
The one that I have now, I think suits my lifestyle really well.
I still have plenty of power and lots of torque when I need it to and can have the occasional fun in the roundabouts.
The AWD is quite nice as well, especially in the wet.
That said, one could argue that in these circumstances I don't even need a 313hp car
Might was well get a Peugeot
So, I don't think that M4 vs 435xi should be a "rational" choice either...
Just get what you think will make you happier.
If money is not the issue & you do have where to play with it, then go for the M4!