That has got to be the most ridiculous, unnecessary and ugly answer to a question that no one on this planet has asked. The regular X6 comes with a 400 hp engine. The speed limit in the U.S. is (at most) 70 mph. What is the point of this thing?
The 400 hp version gets 13 mpg in the city (which is worse than a Hummer H3). And GM cannot give away Hummer.The base engine is a 300 hp 3.0 twin
Car and Driver's observed fuel economy: 16 mpg
The 400 hp version hasn't been tested yet that I know of.