Shawn, it would kind of scare me; I would definitely do my own testing with it first. Here are my main concerns (also, I'm only addressing B&W):(posted 8965 days ago)1) As Thomas pointed out, fill times would be longer. I think the major problem here is splashing onto the top rolls while the bottom rolls are being submerged (for both developer and stop/fix). This is probably relatively insignificant if the tank fills and empties rapidly, OR if development times were substantially long.
2) I know I can knock airbells off the film with my normal setup (a single or double 120 reel Nikor tank) by rapping with my knuckles. I question whether I could do that with a 5-reel 120 tank; I would want to experiment with how hard to rap.
3) Regarding evenness of development, I assume (presume?) the tank gets inverted? If so, keeping a large air bubble (ie, leave some airspace when you fill the tank) is probably important. As you invert the tank, this bubble traveling up through the reels greatly assists in random agitation. If you're really concerned about evenness, you really need to test with some evenly exposed frames; density readings are the preferable way to evaluate.