We tried making the E10 (and E12 for the matter) 1/4" to just make everything smaller, but the forge tooling form both sides meeting in the middle just would not have it, would never make a consistent precise piece. We had engineers banging their heads against this request of mine, so i understand why other brands dont do it - it's not from laziness. You could probably do it with different material, or not cold forging but we dont allow for that in the category on lifetime warranty tools.
Regarding hex bits, I will say it's our own design. At the time, and perhaps still i'm unsure, we were the only ones making forged S2 tool steel stubby impact bit sockets, they are cryo stress relieved as well. Several GJ members field tested various formulations for a year or two before we released our S2 bit series.