Why do people really care about 0-60 mph times? They meant something way back in the day when that was a big test of performance for cars.
Now, 1/4 mile is what you need to look at for acceleration from a dig.
And I wish their would be more tests of acceleration times of 30-100 mph starting in 2nd gear for all cars and for faster cars a 50-130 mph starting in the best gear for each car.
BTW, to the OP a 0-62.1 mph (0-100 kph) time in 5.2 seconds would be about right for a car that did 0-60 in 4.9 seconds.
Now back to the topic at hand, I think the M5 will beat the e92 M3 in acceleration, especially as speeds climb into triple digits.
The M5 is a beast above 100 mph.
But the M3 won't be too far behind