Hi trekkerguy
Don't worry about the wing joint strength. make a good wing joint and it will hold just fine. In the photo below you can see where my glue joint held but ripped out the entire first rib in the wing. This was not the fault of the manufacturer. I had been totally abusing this plane for about 2 months using more than 70 degrees of deflection on the control surfaces and making the plane do things it was never designed to do. [X(][X(] ... That's when the wing decided to snap in half !!!!!!
P.S. It did make a very spectacular swan dive

Dale