This works exactly as described! When I put mine together, I added a bead of caulk between the box pieces and at the top where it meets the underside of the table, just for extra air-tightness. Get the inserts that go with it to make sure the dust goes down through the box correctly.
Mounted on my Kreg table with the adaptor. Captures amost 100% of any dust and debris based on my usage. Very well made and thought out. Requires the movement of the under table crossbars that Kreg provides, but that more than easy to do.