I think 16
All time the highest I know was 15, unless there was one this year. I think that that is shared by Allen Brickhaus and myself. I could be wrong, of course, and I only know for sure from 1993 on. It wouldn't surprise me too much if Bill Fitzgerald or Gary McClellan beat that back in the 70's or 80's. Bill was a real master of the stuff, and his Gypsy still looks like a very good dope job.
I have seen some really good monokote airplanes that I would probably have given very high scores to over the years. Some of the really good ones were RC planes, actually. In some ways it's a less forgiving finish than dope or epoxy, since there is absolutely no way to fix any defects once you make a mistake. With paint you can always fix it with sandpaper, filler, and more paint. With Monokote, you remove it, fix any underlying issues that removing it might cause, then try again basically from scratch.
I have had absolutely no luck with the "new" Monokote, and I really wouldn't know what covering I would use as an alternative.
Brett