Gyro

After building my own shop air cleaner, I can't believe anyone would spend the money to buy one. Having a test on one is a waste of time compared to testing a tool that you cannot build yourself.
I have about $50 into materials for mine and it moves over 1300 cfm. I just used a gable vent fan from a hardware store that cost less than $50, a standard 20"x20" and a 20"x20" HEPA filter stacked on top of one another, 1/2" MDF I had laying around, a switch box, a chain pull switch, some hooks for the box and ceiling and some lightweight chain leftover from some fluorescent lights. After seeing mine, my woodworking friends wish they didn't spend their hard earned money on the commercial units they bought.
If we need a tool test on something, it is not on a tool we can build ourselves.