So I took the M3 out yesterday on 255/45/18 xice3 - cause the kid wanted the blue car....
I took the X3 out today on 255/45/20 DWS06+, brand new from a month ago.
Gunning it from a stop of course the X3 is going to do well with less power and AWD. But considering I wasn't terribly impressed with the xice3 when I first got them, they definitely feel more planted around a corner and I can put power down better coming out of a turn.
The xice3 despite being on the car for the 3rd season, has only around 3k on it max.
Breaking news - old winters are better than quasi all weather tires