These are definitely the cream of the Mustang crop.
Ford spent quite a bit of time in 2014 celebrating 50 years of the Mustang. Some of it was interesting, a lot of it was just advertising. This is thankfully one of the more entertaining bits we've seen, and probably in the running for most entertaining. It features a whole pack of Mustangs from all different periods of the car's history, all going sideways and turning tires into big clouds of smoke. There are some impressively well-choreographed bits as well.
Just a further testament to the value of having loads of works money to throw around.