You MUST glass the wing joint and brace the tail? I have 4 of these light profiles. A Mojo60, 5.2 lbs, 1000 sq inches, flying for 6 mos with a Saito 91 with no glass and no braces. My Mojo 40 tail didn't break when it crashed hard enough to break a wing. My Burrito tail survive a crash that powdered the wing. I have found no tendency for 4 stroke vibes hurting anything on a Mojo of any size. They may not be pretty to some folks but they are for sure tough.