Hack.... I have the omp 540 profile too. Love that plane!!!!
I have found that the plane harriers better with no mix on the wing. You have to Chase the wing until you get it under control but then it's smooth sailing from there. The wing does rock a little but like i said once you get it under control your there. It's real touchy on the throttle. I just blip the throttle when im in the harrier. I have about 1/2 elevator in when i get it right. Steer with your rudder. If you make a turn make sure you add power !!!!
Ask me how i know. hehe.

A good way to check cg on that plane is to do a pin wheel. Put it in a hover ( up high ) and give it full power and rudder. If it goes all the way around your there. If it stop's at 3/4 then move your cg back a 1/4 inch. Once you get the cg right its real easy to hover and harrier.

Hope this help's