It's a drag race between the BMW X6 M and the Mercedes-AMG GLE63 S Coupe. BMW had a better start than the GLE and as you can see, it won the race.
The X6 M crossed the finish line in 12.24 seconds and the AMG GLE63 S in 12.52 seconds. Actually, it's not too large of a gap, at least not to me.
At the end of the day it's going to come down to which badge someone prefers, performance from either one is good enough and it will take a track day to really see the difference, which a small percentage of these will see.