All of the funky angles on the control surfaces (including the tail feathers which I've built, but didn't post pics of) are hard to get right! You have to cut them close, then sand them to the right angle. Also, the leading edge blocks on the wingtips weren't too easy, and the wing tips themselves were a little contrary. The whole thing is not really that hard, but not that easy either. Hard to explain. The instructions don't tell you everything. They're pretty good, but they leave a lot to you to figure out. Also, wile sanding the top of the wing, my thumb went through the sheeting. Had to patch that. Just takes a long time to get everything put into place and glued. There is a lot of wood in that box! Also, remember, this is my first kit, so it may not be as bad as I think it is. Definitely not a 10-15 hour job like the description says. I've worked over 20 hours so far, and the sides of the fuse are being glued to the top as I type. The fuse will probably be finished in 3-4 hours, then final sanding, put in the radio gear, and lateral balancing. Then, take it all out and cover it. We'll see how that goes! More pics to come!!!