Note that the Medusa pistol is no longer made. In fact, there was a lot of talk about Taurus making a revolver that could chamber .357, .38 special, and 9mm luger all at the same time. However, about a year ago this model went from "coming soon" on their web site to being removed entirely.

I don't know why, but no revolvers like this have ever been commercially successful. And the best design in the world means nothing if you can't actually get your hands on one.