I don't know which it may be.....I'm quite sure the documentation didn't specify which it was. From what I've experienced so far, it is not the hardened type.....if it is, I'm not impressed with that type either.
It's not a new product but it is new on my SuperNova Tactical.
Short story, I like the fit but am not yet sold on the anodized finish. If it does not hold up, it will get one of the spray on coatings.
More details at my site.
Most reduced slug loads run about 1300 FPS (at least those from Federal are).
Have you shot any 1 oz. shotshell loads doing 1300 FPS?
If so, and they cycled OK, I don't see you having an issue with reduced recoil slugs.