Has anyone tried them? Apparently they're coated in a dry silicone lubricant, which causes small white marks when they hit something, which means no more not calling hits. They also supposedly boost your FPS, most likely because they're slightly larger than regular .20 bb's, therefore they have a tighter seal.
Here's a video, and a link from Arnies:
YouTube- Gameface Marker BBs review
http://arniesairsoft.co.uk/news2/7782