One should make clear that the Delta a KEHRER and no suction is level, ie dirt / crumbs etc. have yet to be covered by the brush and then swirled into the container. What is not so directly under the brush or too heavy, is not caught.
Battery performance makes a good impression and all that is not lower than 10 cm, to get well under it, but all in all a broom is not indeed so funny, but much more effective.