I'm very curious about these as well. Seems like one of the few hybrids that are really trying to be pure iron replacements in terms of similar length, shaft options, head weight, etc.
I'm wondering about playing the 4 (20 degree) as the equivalent of a 3 iron to slot in above the 4 iron (22 degree) in my set of MP-18 MMCs. I hit that 4i well enough with a decent ball flight at ~190. With whatever club speed that indicates I'm at the point of diminishing returns though, and there's no way a true 3i would make sense. Higher launch, some forgiveness and a better option out of the rough woul