Anything that uses positive charge ions to attract and cling to airborne particulants is a bad bad thing.

Its called the 'black wall effect'. In a nutshell...positive charged ions attract airborne particles...induce the positive charge to those particles...which in turn makes them stick to anything they come in contact with. (that is why in commercials you see them wiping crap off of those rods in the ionizing 'fans'.

So...if you're ionizing your area...all you're really doing is getting your grow's aroma to literally 'stick' to things it comes in contact with.