So its all about prop size?
Does prop pitch have anything to do with it?

I think that i will stick to the outrunners. I belive that gearboxes are just one more thing that can go wrong[:@]
Ive seen some planetary gearboxes that are all sealed up and tidy and just get attached to the motor shaft-those look like they're okay
but those ones that hang out in the open are in my opinion trouble that is waiting to happen.

Just in case you guys are wondering, my landing strip is a dirt road out in front of my house