Thanks, I'll have to do some research to understand the meth responses. Will post back here if I have questions.
As for the sways, I was considering Eibach's offering vs the factory M3 setup. Known differences? As the Eibach is not adjustable, I would like to know if it returns a more neutral handling balance or retains the stock understeer. I imagine the M3 setup is well-balanced already.
Good point on the coils. Will look into that option.
 wait, I might not have been clear. I am considering stock springs on aftermarket shocks. Still might come out equal to or more than those ST coils though. But just to be totally accurate...