If the vacuum is running, she runs
I can't imagine my cat letting me vacuum her. She bolts as soon as the machine comes on, be it a Kirby or an Electrolux. She keeps a discrete distance while the machine is running, although after a minute or two she will inch a little closer to watch the proceedings but with visible tension in her body, ready to bolt the moment it starts actually coming in her direction.
All in all though, she is braver than the cat I had before her, who would run and hide the instant a vacuum cleaner was turned on and would not be seen again until an hour or so after it had been shut off.