Shawn,
Your post raises a related question.
You, and others, have mentioned that "The down side to [stiffer rotors] is that the ride quality in turbulence suffers from being a bit uncomfortable for some people.". Others have mentioned that an advantage of the helicopter over a fix-wing craft is that the ride quality in turbulence is better.
Can anyone comment about the ride quality of helicopters with stiff rotors versus that of fixed-wing planes?