Same for me Jambo.
wouldnt the PPV need a fair bit of grunt to shift the damp air out of every small orifice, such as beneath closed doors
It works though. I used to get mould in corners, behind chest of draw and water would stream down windows and bedroom wall now nothing, dry as a bone even on the windows. It works even with internal doors closed as they are not air tight so we can be sleeping in bedroom with door closed all night and wake up with no condensation.