I have heard, and read, that the early steel loads were pretty poor in performance. I can't really compare them to today's steel loads, as I didn't start using steel when the ban on lead for ducks happened. I intentionally shot ducks with illegal lead loads until I started hunting in Arkansas about 1996. I was hearing so many reports on crippling ducks with the early steel that I decided I was taking the moral high road even if I was a lawbreaker. I won't argue for criminality, I'm just being honest. But, when I went to Arkansas the first time I didn't want to subject my hosts to any embarrassment if I was charged by a warden, so I bought steel. I was shocked at the lethality it had. It was really good, and continues to be, IMO.
Would I like to pull down a few "tall ones" with my 32" SuperFox and some of these? Heck yeah. But, since we have to live with steel I just satisfy myself with it, and with keeping my shots inside it's range of capability. I'm not that good a shot, treblig .........I just pick 'em carefully.
SRH