It should however not be confused with the Mystic 60, which was a much bigger plane (70" wingspan).

I found this text at on old cached page when doing a google search on the Mystic 90:

EZ Mystic 90. Was powered by a Y.S.61 LS on a Weston pipe. She now has a O.S. 91fx 2stroke on a muffler! Very quiet,
excellent throttle response and AWESOME power turns a 12 x12 apc @ 9,700 out of the box on 10% nitro

/Erik