hobby lobby which was the main reseller (and had the best service and warranty) of the falcon3d has discontinued it and has gone with the HBKv2. If that means anything, you may have betterluck with the HBKv2

as far as belt vs shaft, shaft is more efficient, but more things can break when you crash with a shaft driven heli, like the conical gears or something. With a belt drive the belt slips or breaks in a crash =)

another reason for a shaft is for scale models, a shaft can go around a corner, but a belt cannot.

i wonder why they don't use flex shafts for tail rotors like they use in weed eaters and stuff like that. They can absorb alot of impact and can also go around corners, and they don't wear out.... hrm.... maybe I shouldn't have said that and should have marketed it instead and made my millions =P hehe j/k