Roborock S4 Max Review

The Roborock S4 Max is the best all-around robot vacuum we've tested. It consistently performed incredibly well across all of our performance tests, setting itself apart from the majority of models we tested. Amazingly, it is also one of the more affordable models we tested and, in our opinion, the best overall value in robot vacuums today. Check out our best robot vacuums review to evaluate its standing compared to other models in the market.

Performance Comparison

To determine scores for each robot vacuum and identify whether a model deserves special merit, we researched the most highly rated robots, purchased the most promising, then scored their respective performances in six sets of head-to-head challenges.

We expand upon the results of the Roborock S4 Max below, split up into six metrics, each weighted based on overall importance.

Navigation

The Roborock S4 Max started out strong in our navigation set of challenges, a metric weighted to 30% of each robot's overall score due to its importance.

The Roborock S4 Max is a very intelligent robot, leading the test group in many metrics. With regard to furniture avoidance, the S4 Max was excellent. It had no issues navigating around and cleaning around furniture. Unlike many other robots, when faced with an obstacle that it can not go through or get around the side of, it circumnavigates the obstacle to an area it needs to clean. It also worked through our obstacle course efficiently and quickly, posting one of the fastest times without missing or intentionally avoiding areas.

Many lesser robot vacuums struggle with returning to a power station and docking, but the Roborock S4 Max is not one of those inferior models. In our tests, it methodically took the absolute fastest route to the docking station and avoided all obstacles without contact along the way. Even when returning to a docking station from another room, the Max takes the fastest and most efficient route back, even if it means traveling underneath chairs or other obstacles that many other robots intentionally avoid due to difficulty.

One minor drawback to the incredible intelligence exhibited by the S4 Max was its lack of ability to avoid our simulated pet feces in our poo-voidance test. It smashed the small simulated poop and treated it sort of like an obstacle, so it actually returned and tried to tackle it again, making a bigger mess. It also had to nudge the larger simulated poop before avoiding it.

Due to poor poo-voidance, while it's generally a very competent navigator, the S4 Max isn't the greatest for pet owners with pets that struggle with house training.

Home Coverage

On the home coverage set of challenges, weighted to 20% of the overall score for its significance, the Roborock S4 Max performed exceptionally well. It again led the field alongside another more expensive Roborock product.

The S4 Max handles multiple rooms without issues, allowing users to set up multiple rooms and even multiple stories of your home in the app. It also does a great job of spot cleaning and thoroughly handling tasks by making a square cleaning motion. However, there is no repeat function, requiring the spot clean to be requested again if any improvements are desired after a first attempt.

The app allows the designation of virtual barriers and no-go zones, which the S4 not only respected quite well but also did not shy away from and adequately cleaned up to the wall. It even approached barriers under chairs, which many robot vacuums tend to avoid altogether.

When dealing specifically with single rooms, the S4 Max offers great single room coverage and does not miss any part of the test room while cleaning.

Overall, we were very pleased with the Roborock S4 Max's excellent performance in our home coverage set of tests.

Carpet Cleaning

We challenged each model's strength in cleaning carpets with a series of challenges that simulate everyday use. We weighted carpet cleaning performance to account for 15% of every robot vacuum's overall score.

Our carpet cleaning test challenged the S4 Max to measured amounts of rice, oatmeal, cereal, and flour on low-pile and high-pile carpets. It proved it could do a great job cleaning rice, leaving little or nothing behind, but only did an average job when cleaning oatmeal and flour, where it left behind some material and fine dust.

It also did a less than stellar job cleaning cereal off of low pile carpet, leaving a lot behind and even pulverizing some of the cereal into finer dust — although it did a better job on high-pile carpet.

Hard Surface Cleaning

Much like the carpet cleaning metric, we challenged each robot to a set of hard surface cleaning challenges and again weighted it to account for 15% of each one's overall score.

We repeated the carpet cleaning challenges on hard surfaces and again got a mixed but still above-average performance.

The Max did a good job of cleaning rice, leaving little behind, and an excellent job of cleaning oatmeal, leaving virtually nothing behind. However, cereal proved challenging for the S4 Max, as it is for many products we tested. It could not lift or break down the cereal and dragged it around instead.

Flour also proved difficult to clean off hard surfaces, and the Max displaced and left behind what seemed to be most of the flour used in the test.

Pet Hair

This robots ability to pick up pet hair placed it well above average, and just behind some of the best performances exhibited by our test group. It lifted nearly 2 grams of the pet hair used in our test, whereas the best performances were able to lift 2.95 grams, with the average for the whole group about 1.25 grams.

Convenience

The S4 Max earned a very good performance for convenience, our last of six test metrics, weighted to 10% of each vacuum's overall score.

The Roborock S4 Max offers almost everything you could want from a robot vacuum, like in-app remote controls, the function to define no-go zones and invisible walls, spot cleaning, and even multi-level mapping. The robot itself leaves little to be desired from a convenience perspective. However, what it lacks is the robust support of a docking station that has a dust receptacle, like other Roborock, iRobot, Samsung, and Sharks offer as a standard feature. Conversely, the lack of a dust removal system makes the docking station very small, allowing it to fit underneath furniture or hide away nicely.

This requires the robot to be manually emptied with less than convenient frequency and brings down the convenience performance of an otherwise incredible robot vacuum.

Should You Buy the Roborock S4 Max?

Absolutely, yes! No other robot vacuum can offer the balanced performance of the Roborock S4 Max, intelligence, and convenience for a similar price. Even much more expensive models fail to perform nearly as well as the S4 Max. Unless poo-voidance is an absolute requirement for you, we can positively recommend the Roborock S4 Max to anybody shopping for a new robot vacuum.

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