Oh, they have a lot more to grow: those are only sub-adults that haven't even bulked out yet lol I do recommend a male though for whatever boa you decide, and would look into CAs and Nics since they stay small and manageable. PS: Colombian is with a "o"
As for biting, it totally depends on the snake. All of my boas have very strong food responses (I've gotten a few wild strikes when they get really excited and some strikes when I walk by if I'm heating up feeders) but in terms of a strongly defensive (not aggressive) boa my Hog and new baby Argentine female are my top ones. But even when they puff up and open mouth hiss/strike it's not intimidating: they just require a bit more work. My advice with a pissy/strike-y boa is short but slightly frequent handling sessions and DO NOT put them away right away if they start being puffy and striking. They'll learn that that's the way to get out of being held. Another advice: get a baby so you can learn and grow with it as it matures and you'll come to know its personality and when it's not feeling too friendly (snakes have their "off" days I believe).
Also: all my boas (6) all eat F/T without issues.