I'm intrigued by the overall idea, and some pretty high-speed folks have adopted the 5.7mm.
However, until Wolf comes out with 5.7mm ammo (which is supposed to happen any day now...) I can't justify getting a gun where ammo is 40c a shot.
If it drops to 25c/rd (like .45ACP), I'd imagine that would help a ton.
I certainly do want to try one out though.
-MV