I am honestly leaning more towards gpach's point of view except I have one benefit and that is my father in law wants a heli too and he lives at 4800' so if the HBKII or Belt gives me issues I can always sell it to him. As to the frustration and giving up, I crashed my fixed winges an untold number of times before I got reasonably proficient and I have the logic of knowing things don't like to fly at my altitude so watching the habits of say the HBKII will tell me whether or not to get a larger heli if it is tempermental. For example my fixed wing's took me almost a year of tweaking and about $400 to get airborn up here, I just kept trying until something worked knowing it was simply a lack of air density.