I'll admit I giggled at 1:21.
i thought i heard mention of devices like this being deemed illegal. neat but NFA rules aren't to be messed with.
-Triumph, the Insult Comic Dog
I saw this in a movie about a bus that had to speed around the city, keeping its speed over fifty, and if its speed dropped, the bus would explode! I think it was called, "The Bus That Couldn't Slow Down."
The Slide Fire and the AK Bumpski are entertaining range toys - and that's about it.
Anyone in the service will tell you, full-auto fire has very limited uses outside of a support weapon. Also, when you're paying for ammo, the last thing you want is to start shooting full auto "for fun". Would I mind having a fully active selector switch on my rifles? Not at all.
Do I need a $250 stock to let me fire my rifle full-auto using my support arm...just for giggles? Nope.
I guess it's neat for people who have never fired full auto, or seen it's limitations.