Set the Vanquish II up the way that Extreme flight suggest and you have one of the best flying planes found. In a roundabout way I discovered that you really don't screw around with what works. I overpowered mine and decided to use larger batteries then the weight was so high that air speed had to be increased to stay in level flight. After fighting this configuration I reverted the the battery compartment to accept smaller batteries, but because of the heaver motor the batteries had to slid under the wing spar. Once this was done and all trimmed she fly's very well and much slower. Very axial rolls. Coupling is very close.