The best thing to make it stable is the Hiller grips off the Blade CP, but those are $8. But it isn't bad for how much it helps. Move the pushrods in some more than stock, but you will have to adjust them to make sure the swashplate is still level. And it is free. Then the flybar weights on help. With one set of flybar weights and the Hiller grips I think it flys pretty close to a Coaxial helicopter. You might try taking the very thin shims out. I haven't tried that to know what the affects are.

Nick