Roborock is a brand known for well-made robot vacuums, many of which can vacuum and mop as well. The company recently launched a new robot, the $499.99 priced S4 Max, which is very similar to one of the existing robots in its lineup, the $599.99 priced S5 Max.

There are, however, two big differences between the Roborock S5 Max and the S4 Max, and not just the different numbers. Here's how to tell which robot vacuum will based fit your needs between the two.

The Roborock S5 Max can mop, which means the robot comes with a water tank and mopping padsGearBrain

S5 Max

The S5 Max is a powerful combo vacuum and mop, a robot that GearBrain reviewed and tested in its ability to clean floors, as well as work with smart assistant Amazon Alexa. The robot can be scheduled via its app on when you want it to work, and even where as well.

Key to the S5 Max is the ability for the robot vacuum to mop floors via a 290 ml water tank that's built into the robot, plus also the bottom mop pads that fit below on the bottom. You can also control the water tank output through the app, from using no water to a heavy water spray, which helps with more trafficked areas of your home, like a front hallway.

We've tested a number of robot vacuums that can both vacuum and mop, and the S5 Max is actually a standout in this regard. A combo device that handles both jobs well. That's also why it's one of the better rated robot vacuums we've reviewed.

We also think for its ability to handle both, and handle the jobs well, it's fairly priced at $599.99, with the option to pick one in either black or white.

Roborock S5 Max Robot Vacuum Cleaner and Disposable Mop Cloth Bundle

List Price: $565.99

New From: $565.99in Stock

The Roborock S4 Max has many of the same vacuuming abilities as the S5 Max — but for $100 lessGearBrain

S4 Max

The S4 Max is one of the newest Roborock vacuums, a pure-play vacuum that doesn't have any mopping features or accessories and GearBrain recently reviewed. The robot is a very similar device to the S5 Max, a robot vacuum that has a 2,000 Pa suction power, the ability to schedule when you want the robot to run, and also mapping tools so you can create no-go zones for the vacuum — all like the S5 Max. It also shares the same 460 ml dust bin, which means it can pick up quite a bit of dust and debris before needing to be emptied.

But the crucial difference? The S4 Max does not have a mop. That's key to note for anyone who wants a robot vacuum that can handle both vacuuming and mopping. Without the mopping ability, though, you're also not going to have to deal with extra pieces like a water tank, nor attachments like cleaning pads. So that may be a plus for those who aren't interested in a robot that can mop and clean.

The S4 Max comes in just one color option, though, a sleek matte black finish. But we found that was less likely to show smudges or even dust build up, which we liked.

Roborock S4 Max Robot Vacuum with Lidar Navigation, 2000Pa Strong Suction, Multi-Level Mapping, Wi-Fi Connected with No-go Zones, Ideal for Carpets and Pets Robotic Vacuum

List Price: $429.99

New From: $429.99in Stock

You can control both the Roborock S4 Max and the S5 Max in the Roborock appGearBrain

Which is the better robot vacuum?

The better robot vacuum, as we believe at GearBrain, is the one that will best fit the needs of your space. If you have wood floors or floors that can handle wet mopping, the S5 Max may be a better choice — especially if mopping is a feature you're eyeing in a robot vacuum. Additionally, the Roborock S5 Max is one of the better combination vacuum and mopping robots we've tested, and we think it does a solid job at both.

If, however, you're looking for a pure robot vacuum — and have a lot of carpeting in your space, or don't want to bother with a water tank and mopping pads, then the S4 Max may be a better choice to consider.

The S5 Max is also going to cost $599.99, as compared to the $499.99 price for the S4 Max. Since you're getting nearly the same robot vacuum, with strong 2000 Pa suction power, mapping abilities and automatic reaction to being on carpets, it may not be worth spending the extra $100 for the mopping feature, especially if it's not something you're going to use.

That said, we did have a few issues with the S4 Max via the app in that we couldn't adjust the different power settings, nor could we accurately see the battery level. Still, the robot vacuum worked well despite these wrinkles, returning when it needed to power up on its own, and cleaning the floors well.

The decision is really up to the buyer then — a pure-play robot vacuum that has two different color options, or one that gives you the option to mop as well. That's a choice between you — and your budget.

GearBrain tests Roborock S6 Pure smart vacuumwww.youtube.com