Amazon Prime Day can be a great time to pick up a robot vacuum for much less than usual. This year, you can pick up iRobot's Roomba i7+ for only $500, which is 50 percent off its normal price and the cheapest we've seen it. It's not the newest robo-vac in iRobot's lineup, but it remains one of the most powerful. Also on sale are the entry-level Roomba 692, which you can pick up for $180, and the midrange Shark AV2501AE AI robot vacuum, which is on sale for $380.
The Roomba i7+ impressed us when it first came out for its strong cleaning abilities, accurate home mapping and handy clean base. It has 10x the suction power of more basic Roombas, plus dual multi-surface brushes that do a good job capturing dirt, debris and pet hair. After one or two cleaning jobs, the machine builds a map of your home that you can then edit and label in iRobot's companion mobile app. This will let you send the i7+ to specific rooms for targeted cleaning jobs and set "keep out zones" if you have spaces of your home that you don't want to robot to clean.
But the machine's clean base is what sets it apart from other robot vacuums. After each job, the i7+ will automatically return to its base to recharge, and it will also empty its dustbin into the clean base. That means you don't have to empty the dustbin every time, rather you'll only have to change the bag in the clean base about once every two months. If you're someone who wants a robot vacuum that takes almost all of the work out of the chore, the Roomba i7+, or a machine like it with a clean base, is the best option.
Shark's AV2501AE robo-vac is similar in that it also comes with a clean base, and some may prefer it because it's a bagless system. You'll simply pop part of the base off every time you need to empty it, and it snaps back into place when you're finished. This Shark device is actually our favorite robot vacuum right now because it combines good suction power with a clean base and an easy to use mobile app.
On the budget end of things, the Roomba 692 is a solid option. You won't get a clean base, as those are reserved for more expensive machines, but you will get good cleaning capabilities thanks to dual multi-surface brushes, adaptive navigation for better obstacle avoidance and Alexa and Google Assistant support.