That would be fun to have, although with the regulations the way they are it might not be as useful as it looks... A pump would be the only shotgun that you could use this time of magazine extender on, yet I don't think the reduced recoil and improved recovery time would make much of a difference as working the action might A) be enough time to get back on target, and B) might disrupt your aim regardless... then you have to worry about actually acquiring a target with that much extra weight at the end of your barrel... It would be fun though, if for the fact that you won't really have to reload, and to see the look on your friend's faces when you're going through shell after shell while they're struggling to reload theirs.