Zagi-Extreme motor mounts are the only way to go...
100% CNC for a solid and precise fit.
Fits all populare motors 400, Mega 16/15 and Himax 2815 (just bolt and fly)
Tested in the field and this mount will out live your wing.
Zagi-Extreme.com we fly'em hard and fast.
http://www.zagi-extreme.com/Building/Zmount.htm
I love Zagi wings.