My only semi agressive boas are the hog island and sonoran desert boas. Even with the hissing and striking, they will calm down once I get them out of their tubs and in my hands. I have seen very few boas personally that won't calm down with lots of handling. Some may still be pissy but once you get them out of their enclosures, they usually calm down after a couple minutes. The only boa I have seen to date raised from a c.b.b. baby and never calmed down at all was a single female firebelly honduran boa.