I like my Nikor tank, but it doesn't work for everyone, and they are hard to find.
I know more people who seem to like the HP Combi-Plan tank than don't, so I'd figure out what they are doing to make it work for them. If it's a slow fill issue, then the thing to do is pour the developer in the tank and then insert the rack with the sheets and carry on in daylight. I do that when I do PMK in my Nikor tank, because there are issues of uneven staining with PMK if you don't immerse the film evenly.
I think Jobo makes an inversion tank with a plastic reel that works like the Nikor tank, so you wouldn't need the whole processor to use it.