No surprises here, the McLaren is faster.
We probably don't have to tell you that a McLaren MP4-12C can outrun a BMW M4. It had better do with kind of a price difference. So this video that you'll see here won't challenge any ideas that you have about either of the cars, but it is fun to watch. The BMW is technically not stock, but the changes amount to some new suspension components, wheels and tires. These seem to be have been pretty good picks too, and it shows in the corners.
The McLaren is still definitely much faster, especially in the straights, but it's encouraging to see how well the M4 handles the twists.