I too amd looking at the Stage as a replacement for my Cinema. Just yesterday I went to a dealer and listened to a system with Vantages and a Stage (I have Vista's) and the thing that I noticed was that I didn't really notice the Stage. It just seemed to be part of a seamless presentation of sound across the front of the room. At home I "notice" the Cinema.
I am just speculating here, but I believe that in my current system the Cinema appears as a separate source becuase it isn't a perfect match tonally for the Vista's. It was perfect for my Aerius's, but it just seems to be a bit overmatched by the Vista's. My feeling about the Stage is that it sounds better than the Cinema. Not "kicked it's butt" better or any other of those over the top comparison statements that people are fond of using, but as Roberto said, the tweeter seems better integrated and the sound a bit more coherent. Plus I am certain that the Stage can support higher sound levels so I am also hoping that on the big action scenes of movies, where I think the Cinema is starting to struggle, I expect the Stage to handle those better.
I think the Stage is worth the extra, though I haven't heard a Motif. In a smallish room, that might be all you need.
Chuck