Rosy boas are typically docile snakes, and they stay a really nice size (about 40" max for females, & roughly 6" less for males). They do typically go off feed a little
in winter (unlike my colubrids), & being primarily desert-type snakes, do not need additional humidity. Whatever humidity you have where you are, they're fine with.
I do not brumate my snakes in winter...nor do I obsess about their weight when they skip some meals. They'll put it back on in spring. And if you ever breed them,
these are live-born, by the way. Very cool to watch being born...