my only suggestion is to handle the boa a bunch (not right after feeding of course!) if hes really friendly now then you want that to continue. I have a lil nic (was told he was central american-) when we first got him he was a lil fiesty and also when he sheds he is not a happy camper, but i think thats mostly due to the fact that his previous owner didn't handle him too much-

great looking boa!!