I'm not sure just where I saw the experimental Kodak press camera reference; somewhere on the Internet, while I was looking for something else. You will have seen the photo of the nifty 2¼x3¼ Kodak press camera prototype at http://www.geh.org/fm/toronto/htmlsrc/mE13000625_ful.html (it looks a bit like a B&J "Speed Press," but smaller, and it has limited back movements). The picture I recall showed a camera that seemed cruder and was larger, fitted with an odd silvery rangefinder on the side.

Concerning format, the 13:17 aspect ratio of 3¼X4¼ seems a bit more natural to many people than the squarish 4x5 or the longish 2¼x3¼ (or 35mm.) frame, but publications differ in layout. We bought a used 4x5 "Speed" when we found a graphics house that would produce same-size screened separation negatives from "Ektachromes" for an unbeatably low price. Since our two-column picture width was 4-5/8 ins., the 4x5 size was exactly what we needed.

I think it likely that 4x5 filmpack was a bit more expensive than 3¼x4¼, back when film pricing was less related to demand and more related to actual material cost (I should remember, but I don't). If you were shooting a lot of filmpack, over a year that could add up.