I vaguely recall it being annoying to start, but was with my dad so he definitely helped with getting it going. We had a bunch of soccer fields behind where we lived, so we flew it there to avoid any accidents.
It did eventually crash, but was fun while it lasted.
(I don't recall we ever ran the engines. Probably told to wait until we went to a place with room to fly them, and then probably parts were lost before that could happen.)
Speaking of most dangerous toys of that era, I'm troubled to recall that we dumb kids threw around lawn darts, which already looked of vintage design by the time we got them, second-hand. There must still be holes in our garage. We're so lucky no one ever got hit, because now I realize those things could easily maim or kill.
We must've also had figurative guardian angels when (pre-helicopter-parents era) speeding around the streets on our bikes, walking through active train yards, disassembling and repairing high-voltage and motorized appliances and machinery, wandering off on trails and into the woods, etc.
It really seems like there would be bigger problems if one can't assume even that.
It's weird to think that these are considered so unsafe you can't have one anymore, seeing as by that time people were well into complaining about how the nanny state and/or lawsuit-concerned companies wouldn't let anyone have fun anymore.
(it was, to my memory, an annoying and silly toy, like everyone else is saying)