I have 2 BP21's with 8X6 props. For batteries, I'm not sure if I want to use lipos or NiMh. I think the NiMh would be more durable since there is a chance they might get wet. The raw airframe right now is about 450g. I have the motor sticks mounted in the pods, and all surfaces are hinged. My next task is to add the controls for the ailerons. Not sure if I should use 2 sperate servos, or just one in the middle of the wing.
This has been a fun project, thanks for the plans.