I have a 75-1 mix right now I just wasnt sure if I needed to drop it more. I plan on doing the 2 hour break in thing on the ground because our weather is going to be crap for the next week or so but after that I am going to fly with out the cowl for a few flights just to keep good cooling. I have been running my XYZ 50 on the 75-1 and it seems to love it, noticed a 200rpm increase as soon as I changed it. I dont think I will ever make it to 100-1, just cuz I am skeptical...