http://www.unicopter.com/B185.html
Scroll down to the section about the R22 rotor system. There it describes a dynamic characteristic described as "wee-wa". If I didn't know any better, I'd say that describes what is going on with the Bo-105 to a T. It becomes painfully obvious whenever I try to get it into a hover. Apparently it's not just a quirky sim thing.

However some real helicopters do have methods of stabilizing against it. Still I'm not sure how it would be implemented in the sim.
