I started thread a little while back to compare the power and acceleration of the different M3/4 variants comparing 100-200km/h acceleration to remove launch variations. I used the averaged results from different European publications. These were the results:
100km/h -> 200km/h acceleration
9.52 M4 Base (6 samples)
.... ∆ 0.20
9.32 M4 CP (9 samples)
.... ∆ 0.67
8.65 M4 cs (4 samples)
.... ∆ 0.20
8.45 M4 GTS (2 samples)
https://f80.bimmerpost.com/forums/sh....php?t=1376759