Hog Island boa: has hides, uses them 50/50
Hypo Colombian: used hides when she was smaller, doesn't have any now
Jungle Colombian: never used hides when he was smaller, has two in his 4' viv that he uses occasionally since I had them laying around and he's 6+ feet
Albino Colombian: hardly used them when she was smaller, doesn't have any now
Argentine male and female pair: has hides, never uses them
If its a baby boa I'd put some hides in there, it may or may not use them.
Edit: I used the 10-15% feeding rule for my boas when they were smaller without issues, but now I mostly eyeball. You can do both, just don't give too big of meals since they digest a bit slower than balls do. Don't feed more frequently than 7 days.