Bought 1 unit in hopes it would help circulate the cooled air from a window A/C in the small old house I have. AC unit coud not blow cool air the 30 feet into the living room. A pedestal fan I bought helped some but fell short of my expectations. I plugged in the 630 and set it about 7 feet from AC. Wow! Within minutes you could feel the cool air in the LR. The unit was also quieter than the pedestal. After running the system for 24 hours, I was thoroughly impressed with the units performance....so I went out and bought another one for the Master Bedroom. Although the AC unit in the MB worked ok, addition of the 630 circulated the cool air faster and more evenly. I am very impressed with the 630 and intend to purchase a tower fan in the near term. CONS: This is more of a "nice to have" suggestion as I would have liked even thge 630 to have a remote control.