I would say they work assuming you get one large enough for your area. I have an old school Craftsman whole house ionizing filter. It's as big and looks like a radiator somewhat. Defiantly cleans the air. Mounts in the air intake.
The one you posted also has a UV light that would kill any bacteria or virus theoretically.
The Hydrogen Peroxide is some creative language for ozone my guess.
Mine gets quite dirty over a years time and I really only use it for the AC. The ozone that gets created will latch onto the dust, but it needs to land somewhere that would need cleaning.
I just got a mini plug in one for a room. Haven't received it yet.