I've heard the Role speakers, both the bookshelf and the tower versions. I think they are a pleasing speaker to listen to but with a quite different sound than most people might be accustomed to. They are going with a single driver in some form of a transmission line design. However it may or may not be a true transmission line, it does have the smooth bass sound that transmission lines produce and sounds like a much deeper bass than one would expect from such a small cabinet.
I don't know how these would measure on a graph but as I said, the overall sound is quite pleasing. They do sound better than many small form speakers and if space is a critical concern, I would suggest they are a viable option. Like any speaker though, an audition is recommended since no two ears are alike.