Good luck on your STM...

Mine is awaiting covering.

I found the fuselage to be a little to twisty for my taste. I could hold the fuse at each end, and twist, (like turrning a nut onto a bolt.)

I added diagonal bracing from the F3 back, which helped, but still not enough.

If I had to build again, I'd substitute in some stiffer wood for the center stringers on both the sides and top/bottom.

See:
http://www.rcuniverse.com/forum/m_82...tm.htm#8248351 (post 15)