ORIGINAL: flat spin
but have leaned the bottom end out as much as it will go without hesitating. I did this to get the optimum response.
If you leaned it out, then I would say Richen it back up ! seems like they really are very close from the factory. On an airplane this light, with that much power, the high end needle won't come into play too much, just for some vertical climbs and such. So the low end and mid range have to be right, since thats where it will be running most of the time.