After keeping ball pythons for several years, and loving them very much, I am looking at getting a boa strictly for pet purposes (i.e. no breeding, shows, etc). I prefer a medium-ish snake since I have a bad leg and mobility can be an issue. Anything over 10" would be a concern. For this reason I settled on either rainbow or hog island. I am looking for input from owners here on the forum.
What is the temprament of adult rainbow and hog island boas? I read they can be very snippy especially when hungry. Any boa can be nippy when hungry. Generally, if you get one that is pleasant as a baby and you continue with gentle handling, they will be great as adults.
Do they take multiple rats well, versus a single rabbit? I see some owners feed chickens but this doesn't seem to be common? Absolutely! Even adult Colombian boas do very nicely on multiple rats. Rainbows are more arboreal so they have a more slender body than BCI so they should really never be on rabbits. Rats and/or chicks/quail are good for them for life. And Hogs do well with this too.
Is there major concern about transmitting IBD from boas to balls and vice versa? Should I keep the enclosures on opposite sides of the home to minimize risk? Yes there is. Quarantine is an absolute MUST. Minimum of 90 days in a completely separate room. But after that, you can house boas and balls in the same room.
Which is your preference, rainbow or hog island and why? Of the two, I would choose a Hog Island. Rainbows are generally not recommended for beginner boa keepers because they are much more sensitive to humidity requirements. Hogs are almost bullet proof.