I have a new 5-weeks old baby bird, now learning to fly well. Since I also helped feed him from birth, and perhaps from watching & feeling his parents' reaction to my 5888s, he is very comfortable with me zooming one around the room, sometimes close to him! Of course I let an unpowered slowing-down blade harmlessly whack him a time or two so that he "got" that the blades are harder than birds' wings or feathers!
He is not stupid and has already started to imitate the 5888 sounds!
Precisely because these [as I've adjusted them!] are SO controllable and fast and agile [compared to the entry-level S107-types, etc.], I find them wonderful for teaching flight commands like "Come!", "Go, Go!", "up", "down", "left" and "right".
OK, Kiki [the bird] can't fly backwards, but he can almost hover briefly ..... and he does enjoy watching it. Luckily he has not yet found out his wild & crazy mother's trick of knocking one down with a powerful downdraft from a close high-speed overflight pass!