I recently bought a Rosy Boa, after seeking information about them on here. I had replies from Roy Munson, Tricksterpup and Starsevol among others, but not one of them, that I can remember, said anything about them being nippy, until after I had got her home
That being said, I have handled her at least 6 to 8 times now and not once has she tried to chow down on me, but she is a great strike feeder, just a whiff of mouse and she's on it
I think it's like most animals, each one has it's own "personality" if you like and I think I got really lucky with my girl