I've never used one, but I've watched the guy who invented them using one at the big flyfishing show in Somerset, New Jersey. He really knows how to handle it, and the vise shines when dubbing a body. He spins the vise to quickly and evenly wrap the dubbing thread onto the hook shank. Aside from that one particular use, I don't really see much of an advantage to it. The inventor also uses some special spring-loaded bobbins while wrapping the dubbing, which he sells. I think you would need these to use the vise like he does, and they aren't cheap, either.
There are a lot of nationally and internationally recognized fly tyers at the show, and he may be the only person that I saw using the Nor Vise. I don't recall any of the other professional tyers using it, for whatever that's worth. The big barrel behind the actual vise looks like it might get in my way.
Maybe you can check YouTube or his website and see if there is a video of him using it.