This robot vacuum conquers the toughest room in my home and it's $350 off for Black Friday

ZDNET's key takeaways

The Dreame L40 Ultra is a high-end robot vacuum and mop available for $1,500, though you can get it for $1,150 with a $350 couponThis Dreame robot vacuum doesn't disappoint in performanceIt has strong suction power, thorough cleaning capabilities, an extendable side brush and mop pad to clean corners and edges, and an above-average mopping featureThe downside is that the Dreame L40 Ultra isn't cheap.

What's the deal?

The Dreame L40 Ultra robot vacuum and mop is on sale. An early Black Friday deal drops its price to $1,150.

Also: The best Black Friday deals live now

Pet hair is one of my biggest grievances at home. I have a mixed-breed dog whose DNA test confirmed that he's a mutt (not a border collie, as most people believe) made up of mostly high-shedding breeds. This makes it fun to test how well robot vacuums tackle his pet hair, which is easily finds its way into corners where robot vacuums don't always reach.

The Dreame L40 Ultra robot vacuum and mop is the latest to tackle my home's pet hair piles, and I'm glad to say it's done so successfully. 

Sweet Luca's black-and-white coloring means I must vacuum every day to avoid seeing gray clumps of hair everywhere. The Dreame L40 Ultra expertly tackles even the corners other robot vacuums don't reach with a side brush and mop pad extending up to 20mm.

This allows the L40 Ultra's side brush to reach corners and wall edges and sweep them towards the robot's nozzle. 

I performed controlled testing with the Dreame L40 Ultra before unleashing it to clean my entire home's floors. 

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In my tests, the Dreame L40 Ultra picked up 94.5% of debris, a great score that few models can beat. It stuck to its map about 85% of the time, which is likely why it can maintain such a high cleaning efficacy. Other models I've tested average between 65% to 75% in navigation, so 85% is pretty impressive.

The Dreame L40 Ultra successfully avoided obstacles like socks, my desk's panel legs, and charging cables. I realized it's so good at cleaning thoroughly while avoiding cables that I gave it the toughest job: cleaning my office daily. 

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My home office is where I keep all sorts of review units, from portable power stations to smart home devices. It's also where my dog sleeps, naps, eats, and drinks water. While different items always come in and out of my home office, two things are constant: pet hair and chargers.

I've never been able to run a robot vacuum daily in the home office because the floor is always strewn with charging cables, my dog's chewed-up toys, and random kibble. Robot vacuums typically get stuck on these items, so while I run my vacuum daily in the living room, I make a virtual boundary to keep the vacuum out of the home office, which I then manually vacuum and mop.

The Dreame L40 Ultra robot vacuum and mop has been running on a daily schedule in the home office for over a month, keeping the 300-square-foot space clean and free of pet hair with no effort on my end. This has helped my allergies immensely, as even the air purifier in the office runs less often because the room has less pet hair and dust. 

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The L40 Ultra's biggest fail in my tests has been pet waste. I own visually accurate fake pet waste for testing robot vacuums' obstacle avoidance features.

The Dreame L40 Ultra has AI-powered visual recognition to identify obstacles like paper, cables, socks, shoes, and pet waste. The robot scored 65% in my pet waste test, mostly because it kept pushing the prop pet waste around, which would be disastrous if it were real.

The Dreame L40 Ultra also vacuumed up one of the props and destroyed it with its roller brush. The vacuum kept running and finished its full cleaning cycle, so you can imagine the shocking abstract painting you'd find on your floors if this had been an actual pile of pet waste.

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That said, the 65% score isn't dire compared to other models I've tested, as the Dreame L40 Ultra tries its best to avoid pet waste and even takes photos of it for you to view in the app.

ZDNET's buying advice

The Dreame L40 Ultra is one of the smartest robot vacuums and mops I've seen, but the brains will cost you a pretty penny. At the $1,500 retail price (or even the $1,150 deal), this isn't an entry- or mid-level robot vacuum but an investment in your home's cleanliness and your personal convenience.

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I'd recommend the Dreame L40 Ultra if you're looking for a high-end alternative to a Roomba that'll keep your floors clean, down to every edge and corner, and offer a reliable mopping solution for hard floors.