What I heard was the short barreled rifles like that can have reliability problems if stuff is done that changes the backpressure on the gas system. Most suppressors would add a lot of backpressure. There are suppressor designs that meant to have low back pressure. I would have thought one of those would work.
That kind of turned me off on the design, but I can still see how the very very small package would still be pretty neat to have. Classic Firearms had a giveaway going with the 7.62x39 version.