These are both older examples of the performance crossovers.
The BMW X5 M and Mercedes-AMG G63 represent two different takes on what it means to be a performance crossover. If you plan on leaving the pavement, then it's hard not to choose the Mercedes, but the BMW might have the edge for comfort on a road trip. This video captures two drag races between them.
Gallery: Mercedes-AMG G63 Races BMW X5 M
The performance-focused crossovers in this clip are not the latest examples of their kind. The G63 is the previous-gen model that packs a 5.5-litre twin-turbo V8 making 563 bhp and 561 lb-ft of torque. It uses a seven-speed automatic with full-time four-wheel drive, in addition to front, centre, and rear differential locks.
The X5 M packs BMW's 4.4-litre twin-turbo V8, and this application of the mill offers 567 bhp and 553 lb-ft. The drivetrain consists of an eight-speed automatic with all-wheel drive and a limited-slip centre differential.
In the first race, the BMW wins without much effort. The X5 M covers the quarter-mile in 12.48 seconds at a speed of 110.87 miles per hour. The G63 is slower by requiring 13.93 seconds to complete the distance, and it's going 100.47 mph at that point.
There are many explanations about why the G63 might be slower than the X5 M. One factor is that despite having similar outputs, the Mercedes weighs quite a bit more than the BMW. The vehicles' tyres and selected driving mode would also play a role in the quarter-mile time.
The results of the first race make Road Test TV ask if an error by the Mercedes' driver could be the reason for the slow time. Watch the second run for a better idea.