Junk. Potentially will foul up the internals of the gun. What i see on the intertubes indicate that they aren't all that good quality in terms of smoothness/diameter specs. Low grade BB's for low grade guns that would likely break before they foul up internally.
Airsoft is an honor-based activity. People should be taking their hits and calling them. If they don't - unload a mag on them - of good quality BB's. No need for marker BB's to mark up peoples gear like in paintball.