I am aware that most of them are consumed... but according to your intuition, who is more likely to use them more frequently or at least have used it once?
I am 100% against the taking of them, no fighter should have to take them to be on a level playing field. However the drug testing authorities are with regard to catching PED users, many steps behind the drug providers and users in catching them. Certainly at the top of our sport there is big big money to be made, so the risk vs reward issue of taking PEDS comes into play, especially if you know the penalties from getting caught are not draconian. So i would guess that means that i am sure most of those boxers probably have used steroids at some point, even if used therapeutically but outside the permitted rules.
I would say Davis, since he has a pretty unusual physique and a lot of resources to hide it, and Cruz, since he is a marginal guy with nothing to lose, seem likely. Stevenson, Garcia, Haney, and Lopez are still at the point they don't need them yet. Loma appears to be aging naturally (in fact aging kind of fast).
Performance enhancers come in many shapes and sizes, but actual steroids? I'd reckon very few lightweights would be taking them. Diuretics for weight cuts and things like EPO for endurance sure, but flooding your body with testosterone when its already hard to make weight seems unlikely.
Went with Tank as the likely from the choices above, not that I think he's on them....just that I think he'd stupid enough to do so.