for the longest time i wouldve said the gazelle. the very second i touched the collective, the thing would go full-retard and id have no control. if i was lucky, i could hold on for a few seconds- but like with a mechanical bull, the ride is always short and any sense of control is an illusion. those flights would end with something snapping, and me plummeting to the ground. most takeoffs pretty much resembled looney tunes tasmanian devil...on meth.
but then i checked the axis tune, and just needed to invert the collective. i was instantaneously going from 0 to 110% the second i budged the control. once i got the curve oriented, everything has been copacetic and the helo has been the most fun module ive had to fly
used to end up veering off to the left into a ditch when taking off the l-39 in the persian gulf. not so much anymore