What's the best modern BMW M car?

I compare the current BMW M2, M3, M4 and M5 on both road and track to see which is the best modern BMW M car.

BMW M Models - Range of Luxury Powerful High-Performance Cars

BMW M Models Lineup

13 Things You Learn After Driving the BMW M2

BMW M Models - Range of Luxury Powerful High-Performance Cars

Special feature: The best of BMW M

The New BMW M2 Could Be the Best M Series Car Yet – Robb Report

Driving the world's greatest BMW M cars: TRACK TEST

Best BMW M cars ever

All-new BMW M3: facelift model snapped testing