Yup, the 1" intake plus the added restrictions of the manifold and valves and the 3/4" hoses makes a one pump solution impractical. That's why most guys have gone to the T1200 with a separate 1" intake for each pump and a 1" line to each bag. It's more work and more expensive but you see dramatic improvements in fill times. I chose to go with something more budget friendly and just one intake and I am satisfied with the results (for now). :)