That's all about frequencies. 1:10 shocks are way too big to absorb higer frequencies from the contact of the road, so we need something else to absorb it. Carbon fiber was a good candidate. Now there is also a matter of hysteresis. On this point I think Mg is between CF and Al, that's why I like it. I have the flex chassis, which is quite stiff I think, I can't get the weight now but I will try to get it soon.