I like my combiplan enough to own two of them; so I can develop twice as much; I stagger them about five minutes apart.
It takes a little more than 1L of chemistry, but I use pyrocatHD and it's cheap. A larger volume of liquid will maintain temperature better without a water bath. I load the holders without the guides, just feel the film into the slots, then run my fingers over the edge of the film to feel the spacing like on a mod54.. It is annoying slow to fill and drain, but that hasn't affected image quality at all. After the fixer has been in the tank for a minute, the top comes off and it's a daylight dip and dunk for the fixing and wash. Push the film retainer clip in gently and agitate gently and film won't fall out.
It's very functional for me, but there is room for improvement if someone were motivated to improve upon it. I'd make the film carrier/holder one-piece plastic to make it less wobbly, and have better drain/fill spigots. If you get one, use it several times before jumping to a conclusion. You can always sell it for what you paid for it if you buy reasonably carefully.