M5board.com has posted their own spy video capturing several prototype BMW 6-Series doing high-speed runs down the Autobahn. Gustav, the forum’s administrator, was lucky enough to be a passenger in a G-Powered BMW M3 E92 so they were able to easily keep up with the 6-Series prototypes.
During the 10 minute video below you will see that they easily reach speeds of around 155mph (250 km/h). As a bonus, check out the video of the G-Power M3 get up to 188mph (303 km/h). Enjoy!