What a difference a prop change makes!
I get You Billy Hell, not much talk of going that big. I don't spread it around much 'cause the "smart guys" tell me how it's all wrong.
Lots of guys figure a .40 gets a 10x6, and a strong .46 or .50 might be able to handle a 11x7, but 12, 12.25 or 13 inch props? No way. If I remember right, they quote the manufacturer's RPM and Torque numbers, and kindly explain that I'm not "in the power band" and that I'm not "getting all I could".
Then I just go and pull my plane off the deck in 3 feet, go straight up 'til it's a blip, flat spin all the way down and then pull into a hover a 1/2 throttle (well sometimes it actually works). They usually shut up.
I've got a reputation as the guy "with all the props", my bottom drawer of my flight box has probably 30 props in it. I love to experiment. I figure if it flies well, temps don't go too high, and the plane has ground clearance (that CAN be modified at the field!) I go for it.