Mine has a straight trailing edge Well I'm using a 53 two-stroke and it had unlimited performance, hovers bit below half throttle. My cg is right on the standard freestyle plan and the battery is at the rear of the canopy. For flying, little coupling in knife-edge, elevators inverted stable yet undo-able upright, if you see in the pictures and movies they NEVER do upright elevators... I think this tells us something. For the ailerons, I'm using the standard ailerons and it does high alpha rolls, on low rates. For what I'm doing I'm perfectly happy, it still blenders and does all the 3d moves but really you cant hide the fact thats it a 40 sized model, fly a 2m ship then fly this and theres no comparison but I'm still happy with how it flies, a great we f3a practice model.