Dreame is one of the many newer robot vacuum companies that has been competing for the top spot. One of their flagship vacuums, the Dreame L20 Ultra robot ... extends to the side to clean farther ...

Nearly everything that made the L20 Ultra great has been improved for the Dreame L40 Ultra — including enhanced suction, improved roller brushes, and an extendable side brush for improved reach.

When the robot encounters an edge it can't get under, it will even extend the mop out to the side, to clean under the surface. Right now, the Dreame L20 Ultra Robot Vacuum is on sale for $800 off ...

The Dreame L40 Ultra is a high-priced robot vacuum ... a value model that had a lot of high-end features for the price. But the L20, a higher-priced model, was a disappointment.