Are you set on a .40? The 60 size big stik kit and the .60 size Super Sportster fly way better than their 40 size counter parts. All of them are great, but the .60 size has more stability and I have a lot more fun with them. I prefer a built kit, and the stik is a fun plane. Build the wing flat, with no dihedral. It will not have any adverse affect at all. I can still fly mine as slow as anyone can with dihedral, but it rolls better and is a lot more fun to fly. I have a friend that will not listen to anyone and put dihedral in it, and now he wishes he wouldn't have.

Good luck. Build any you want, for next week you will want a different one. Build that one too.