The Winners of Our Geekiest Tests

When we test equipment, it’s not enough to just learn which models are best. We want to understand why.

Understanding why some products win our tests and others don't is the most challenging part of our jobs—but it’s also often the most fun. To figure out the secret behind robot vacuums, Lauren stuck each one in a storage closet, dusted the floor with flour, and took long-exposure photographs of their movements. Some moved in methodical grids while others bounced around randomly and left behind lots of debris. We apply that same rigor when testing knives, too. We’ve looked at them under a microscope at MIT and done days-long temperature tests of French press coffee makers. Read on for more information on the winners of some of our geekiest, most illuminating tests. —Kate Shannon, Senior Editor, Tastings & Testings

Testers loved this machine, which had a slimmer, compact footprint and shorter stature and thus took up less room on our counters. Its cooking basket was roomy enough for 1 pound of food and had a completely nonstick coating. We also liked that the bottom of the basket could be removed for even deeper cleaning, if needed. Its digital controls and dial-operated menu made setting the time and temperature easy and intuitive. It stopped cooking as soon as the set time was up, and its drawer-like design allowed us to remove food without exposing our hands to the heating element.

This mixer aced nearly every test, with the exception of the high-hydration pizza dough, flawlessly completing everything from the most basic of tasks (such as whipping two egg whites) to making enough frosting for a three-layer cake. The speed controls and tilt-head lever were straightforward and simple to operate, and the bowl and attachments were easy to put on and take off. We do wish that the bowl had a handle and that the price (about $250) was a bit more relative to the mixer's size (the KitchenAid Classic Plus Series 4.5 Quart Tilt-Head Stand Mixer is about $230); however, if you want a smaller machine, this is a great option.

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Like our favorite highly recommended full-size Dutch oven, this smaller pot’s light-colored interior and low, straight sides allowed us to easily monitor browning, and its large looped handles made it easy to move, even when filled with 4 pounds of short ribs. It had excellent heat retention, and French fries emerged golden brown and crispy. The one drawback? Its shorter stature meant that a pile of short ribs were slightly cramped; however, the end result was still excellent.

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This model made great food and had a clear LCD interface that was easy to use and always told us exactly what it was doing, whether it was preheating, pressure-cooking, slow-cooking, or keeping warm. We also appreciated the sensor that alerts you when the lid isn’t properly sealed and the brace that prevents the gasket from drooping. You can also lock the control panel, so no one can bump it and accidentally cancel or adjust the settings.

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This D-shaped robot uses a special set of lasers to scan and map the room so it can chart an efficient path through the space. Because of this, the Neato takes one-third as much time as other robots that cleaned more randomly to thoroughly cover a room. It hardly bumps into walls or furniture and easily navigates from room to room without the help of virtual gates or physical barriers. Testers loved watching this robot’s efficient, grid-pattern cleaning and liked that the robot largely steered clear of major obstacles, though it still occasionally got caught on cords or under furniture. Its unique shape allowed it to cozy up to walls and fit perfectly into corners—key spots every other robot missed.

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Our favorite santoku wowed testers of all abilities, who raved that it felt “agile, sharp, and really good in hand.” “Solid but light,” it made “fine, level cuts” with “great precision and control.” This knife features an asymmetrical blade with a 70/30 bevel that the company hand-sharpens specifically for either right- or left-handers.

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This smart alarm was easy to install, and its app was simple to set up, navigate, and use. The user-friendly app made it more convenient to silence alerts than on a conventional alarm. It did a great job of distinguishing between low volumes of less serious smoke while we were burning toast and high volumes of more serious smoke while we were searing steak. And its alerts and alarms were relatively easy to silence through the app, though occasionally we had to wait a minute or two to receive the alerts or move closer to the unit to silence them. If your Wi-Fi goes out, the alarm will continue to function as usual—even communicating with other Nest devices as long as it is still drawing power. It will not, however, be able to send alerts to your phone, though you will still hear the alarm within the house if the unit detects smoke or carbon monoxide. In addition, we loved its extra features: Its nightlight, automatic testing of its battery life and sensors, and ability to connect with other Nest Protects are all big bonuses. It also complies with the latest standards set by UL, a global safety certification company.

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It takes slightly longer to say “OK, Google” than “Alexa,” and the Google Assistant is a bit less natural than Alexa in responding to casual human speech, but this device has all of Google search at its disposal for seeking answers and resources for you, and it always lets you know the source of the information being shared, providing links if you want to know more. Its gesture-only and facial recognition features are useful, and Alexa can’t do them (yet). A major downside is its user-unfriendly app. While this smart display’s function is mostly speech-based, you use the app to set up the device, add people and smart devices to the account, keep shopping lists, and other functions.

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