PLEASE use actual plywood as a wing joiner and not the lite ply provided. If you can, also add some additional wood near the rear spar. You could also glass the joint. I say this because I had the wing on mine fold and totalled it. It was eventually replaced by Goldberg when I sent the centre section of the wing in to them. It is a weak area and should be reinforced. This was after only the usual bounces on training and no serious bumps or crashes.