Brad, the fit and finish of the Kumagoro is not quite up to that of the Yoshikane, or at least that's the way it was three years ago when I briefly had a Kumagoro. It may have change in that time.
The core steel in the Kumagoro is Takefu V2, which is an excellent steel, but the SKD tool steel in the Yoshikane hammered is just a tad better in terms of edge holding. (BTW, Takefu V2 is the core steel in the soft iron clad Kochi.)
As you will be using it in a home environment, the differences are pretty much academic, as you'll likely not dice forty pounds of onions at one time.
Either knife will suit your needs well, but since you seem to be leaning toward the Kumagoru, I say go for it. Keep in mind that there's always the B/S/T sub forum, in case you decide to sell it and move to another knife.