I should mention that I converted my SS40 to have quad flaps, just like the larger SS60. With CROW deployed, it'll stand still in the air with a 10mph wind.

My SS40 gained a little more than 1/2 lbs going from .53 to .75 and I didn't notice any change in its flying characteristics, other than now it hauls ass on the verticals. 9 Oz. is not going to change the way this plane flies drastically. What it does allow you to do is mount rudder and elevator servos near the tail for more positive control.

OTOH, from what I've seen it fly with a .53, I have no doubt the plane will fly excellent with the OS .46FX. With such a light airframe, this plane is a barrel of fun anyway you power it.