chondar,
bruce is right, the 40 la will fly it but not well. I put a tower 46 in my Kaos, after pulling alot of hair getting that tower motor to run right, I have a nice flying airframe. Stay with a 46, and not the 46 la. Bigger motor but still not a powerhouse. .46 AX or equiv., maybe even a .55 AX, what do you think bruce?