While it's not exactly fair to compare a sporty 2-door coupe like the BMW M4 with a large family estate like the Audi RS6, the two did put on quite a show during this drag race.
With the M4, AK Tuning fiddled with the ECU to squeeze out another 60 horses, while the DBR Audi RS6 Avant is putting down a very impressive 750 HP, almost 200 more than stock.
Speaking of stock, there's really not a huge difference between the two cars in terms of 0-100 km/h (62 mph) acceleration times. The RS6 will ideally hit the mark in 3.9 seconds, while the M4 needs 4.1 seconds.
In this case however, we're looking at a rolling start race, and an even bigger power discrepancy than before, so we wouldn't blame anybody for betting on the RS6 to absolutely obliterate the M4.
Something to keep in mind - the M4 weighs roughly 1,590 kg (3,505 lbs), while the RS6 has a lot more meat on its bones, at 2,025 kg (4,464 lbs).