I mostly agree with Lemans_Blue. Very close performance between the two tires. Everyone has their brand/country prejudices, but objectively both tires are excellent.
As TLud says, the Michelin gives more warning before breaking away. The Pirelli has a littler sharper response but is a little less forgiving at the limit.
I have accepted a new position at Tire Rack and am no longer in the sales department. firstname.lastname@example.org
is available to assist with M3 questions.