This mike, as well as the other ribbons by Royer and Coles, interest me also. I haven't heard them, but I hear rave reviews from people using them for stringed instruments that say all the "right words" that I'm looking for, and the frequency response curves seem "right".
There is a guy who posted about these ribbon mikes called "jnorman" who seemed credible (i.e. sane and rational and experienced) You could search for posts under his name.
Let us know if you try them. All it takes is mucho moolah !
Peace,
Rick