Youngsters can indeed be nippy. I have a young female who is 30 grams of pure malice. My other two are extremely docile. I'm hoping Juno will grow out of it.
That's really the only con I can think of other than they are not display snakes. They stay hidden most of the time.
as kasey and whitney had said they can be nippy as youngsters. but.... anything with a mouth and teeth can be nippy. i have worked and breed them for years... and personally never been bit by a single KSB and honestly wouldnt put them in that category. when i seen the thread name the VERY FIRST thing that popped in my head was... there really are no cons that i can think of. as jarrett first said.