Chris, it all depends on the type of day you're having up there,,, thick air-thin prop,,, thin air-thick prop. It all boils down to test-practice-test-practice-test,,, and more test-practice,,, so on and so on. With all the different props that are available its a good thing to have a few in the box for those different types of Race/practice day conditions. Go with 7.8 or 8.0
The other alternative,,, Wood Props
IF you are able to, carving out a wood prop can be very rewarding and its a whole different animal [sm=shades_smile.gif]
Cady's website has some info there about them for starters(I think?)
BV