Wilfbiffherb, as the owner of a fully movable Super Press 23 (have the GG back and all the crap you can get for the thing) I have been eyeing 4x5s like the Linhof and Horseman for a few years. I have no intention to go to 4x5 but 6x7 or 6x9, oh ya.
Be picky on what you can pick up unless you know you can handle well worn equipment and intend to learn first then upgrade later. Personally, I would prefer using the movements on a camera designed and intended to be "moved" versus something like my Press camera that "can" move but all you get is knobs to loosen then slide it to move. Not very precise at all nor smoth. A view camera just has to be adjusted easier.