Looks interesting. I'd certainly buy one or two, and depending on how the steel performs in use, potentially more.
I wonder if the Japanese makers have investigated the question of whether a slightly different cladding stainless grade might allow for a harder core steel treatment? I understand the heat treat for laminated steels needs to take into account the response of both steels.
I actually quite like the relative toughness and ease of sharpening of the 'softer' HAP40 core, clad blades. No surprise since I have five of them. But it seems a lot of users report that they like the higher hardness of the knives featuring the monometal REX45 Crucible version of this steel grade. (I personally haven't tried REX45 yet.)
Also, I'm glad to hear the Wharncliffe Delica is being considered for this sprintrun. Of late, the HAP40 model has been my most used knife from the Seki family. It's an outstanding work knife, and a design I'd be particularly interested to try in different steels.
The next two Seki models I'd be most interested in would be the Dragonfly and the Stretch 2.