Plan on getting a Goldberg Extra and one of these. I plan on the Extra coming out at less than 9 pounds and I'm wondering what prop I would use. Kinda early to be worrying about that but I want to know if it'd pull the Extra vertical easily. I would probably start out with an APC 16x8 but I could probably get a custom made Bolly 17x6 or 17x8. I figure the 16x8 would turn about 9000 and the 17 inchers to turn from 8500 to 9000. Any recommendations? I was wondering about the tuned pipe version too. Any info?