I have the one reel Jobo tank with the 4x5 reels. I find it's a pain to use as an inversion tank. It takes a ton of chemistry, about 1.4 liters otherwise you will get uneven development. I found I can load the reels much faster by hand than by using the loader base. I never could get the knack of the thing, most often the film simply pops out of the grooves as it tries to go around. I figured by the time I got the thing loaded and closed up I would already be halfway through the process if I was using trays. Plus, using inversion agitation I've had problems with the emulsion sloughing off at the edges. I personally decided that using the tank with inversion is not worth it but you might decide otherwise. If you are set on using the Jobo tank manually try the roller base. It requires far less chemistry but you have to roll it continuously. The one reel tank is awkward to roll since it's so short but I think the two reel tank would be much easier to roll.(posted 8404 days ago)Many others on the large format message board have suggested Unicolor drums with a Beseler motor base for rotary development but I just went back to using trays for the time being.