1. Nope on tire wear, the M4 front Primes still look good. I tried the 500k and got fast laps but consistency wasn't the same. With the 300k it was easier to drive, drive fast and also have fast consistent laps. Again, this is what works for my driving style and for my tracks I don't see a need to use 1mil. Most of the setup sheets that I've seen on Petit RC database are using 300k & 500k pretty evenly.
I will agree though I can't ever see using anything under 300k for this car.
When our track opens back up after Christmas break, maybe I'll try 500k again, but just didn't feel it or see it in the lap times.
I tried the Thornhill setup that some people raved about and it did not suit me and the track.
2. The toe I carried over from the Thornhill setup and that was the only thing I really kept or stayed with and for now it works. I'm debating about going back to 0-0 for the rear hinge blocks and test it back to back on the track during mid week practice night.
I also tried out the 12* Exotek Casters and didn't like them for current layout so went back to the 9* Casters. I could possibly see the 12s working at a rougher indoor track or at an outdoor track.