Got to say/simple update post.......
I've had the 312s on now for over a year. I run the Stoptech Sport slotted rotors f/r with EBC Yellowstuff pads, Motul RBF600 fluid, RS3 brake ducts (modified), as well as Neuspeed ss brake lines. I've beaten on it as a daily, hooning in the mountains, and for a few days on the track at VIR. This combo works great. I still think for the heavier awd wagons that the R-size 340s up front is the way to go for max heat dissipation and I likely at some point will do the shopdap TTS setup up front.