Unsure if I should get her.

[Caspian]

Personally, I'd go ahead and get them. You get one that you want, and the other gets a good home. It sounds like your friend wants what's best for the snakes - in other words, a responsible and caring owner - and that's you. The big girl, in my opinion, would make an impressive display snake (In a display cage). She sounds huge! She may never be able to be handled... then again, if you take it slow, she may mellow out eventually. I have three mustangs, that came off the range wild and untouched. Not snakes, of course, but two of them, with time, patience and consistency, are as mild or milder than any domestic-bred horse now. The third has some major security issues, and I think some psychological issues... as well as a genetic defect, a club foot, which is probably the source of the other two problems. She will never be mild, and I would never trust her enough to put a rider on her unless they were extremely experienced and knew what they were getting into. But even she has come around to where I can handle her, despite being untouched for the first four years of her life.

I'd go for it, and just try to work with that Sub-Saharan when you can. Maybe, with time, she'll settle down - and if not, she'd still make an impressive conversation piece. And you can go look at what nature produced, and see how different it is from what selective breeding can do.