I don't think you will be disappointed, I have the V1 and they are awesome. The holes from Kevinlee premium is as good as Ksblade, but the advantage of Ksblade is their ergonomy, and also very easy to align against a scribed line, since the prongs are slightly rounded at the end.
Edit: I saw you wrote diamond, I have the French irons, but from what I've seen on Instagram their diamond stitching irons are also awesome.