Surprised no one mentioned Metzeler Z6 Interact or the new Z8. I loved the Z2/Z4 on the C10. IIRC, Metz & Pirelli have the same parent company and I wonder if the tire have very strong similarities.
I'm with you on the Metzler z6 interact. Had a set last summer . Best tire I ever rode on. Only issue wear length and no wear bars. Just barely got 3k on a set. Unexpectanly wore them to the cord in the middle of Utah. Spooned a set of PR2s in Salt Lake. PR2s felt predictable, not as smooth or sticky as the Metzler. Next set thinking of trying the Mezterl Z8 Interact.
Past tires Michelin PR2, Perilli Diabla Strada.