I had a small towel (it was completely black) in my waste tank basket the other day....I'm sure it ate up a cfm or two. Not only that there was about a half inch of debris in it too. I'd say it had been a week or two since I had cleaned it out.
The first pics have three 2" inch barbs and two 2.5" barbs, this was for the standard Vortex and AT units and some Steam Action units.
The new AT's come with twin 2.5" from the get go, but they do have a third 2" "spare" port avail. that is capped, So Michael Schoeny opened his up to 2.5" and requested an ALL 2.5" Super Vanifold to optimize his setup.
I will say when you hook up three 2.5" hoses to two 2.5" hoses, all powered by a single 5.5" hose it's down right impressive.