I played with one at Rifles Only at the Bushnell Brawl, and talked in depth with Johnny P. about the design and mission of the can. Long story short, it's definitely innovative and well designed. No gas blowback at all, which surprised the hell out of me, and the design of the can radiates heat differently. It's not as quiet as some, but on the list of "must haves" for the application of this can, that is pretty low on the totem pole for a multitude of reasons. The modularity of the can is superb.
It's definitely on my short list, and Johnny is a hell of a guy.