Between the S9 MaxV Ultra and Roomba j9+, the S9 MaxV Ultra comes out ahead in noise and mopping, while the Roomba j9+ wins on battery life. Overall, the S9 MaxV Ultra scores 85.1 and the Roomba j9+ scores 49.8 on our Mars Score.
Which should you buy?
The S9 MaxV Ultra is the clear pick on raw spec strength, leading by 35.3 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
Pick the S9 MaxV Ultra if you care most about noise and mopping. The biggest gaps in its favor are noise, mopping, lidar, among others.
Pick the Roomba j9+ if you care most about battery life. Its strongest claims are battery life.
Both ship with comparable self-empty base, ai obstacle avoidance, so those specs don't separate the two — focus on the differences below.
Bottom line: the S9 MaxV Ultra is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why Roborock - S9 MaxV Ultra wins
- ▲Noise — 3.00 dB less. 65 vs 68.
- ▲Has Mopping.
- ▲Has Lidar.
- ▲Suction: 22000 Pa vs 0 Pa.
- ▲Water tank: 300 ml vs 0 ml.
Why iRobot - Roomba j9+ wins
- ▲Battery life — 11.11% more. 200 min vs 180 min.
Spec comparison
Cleaning
| Spec | Roborock - S9 MaxV Ultra | iRobot - Roomba j9+ |
|---|---|---|
| Suction | 22000 Palead | 0 Pa |
| Mopping | truelead | false |
| Water tank | 300 mllead | 0 ml |
| Dustbin | 350 ml | 500 mllead |
| Carpet detection | true | true |
Navigation
| Spec | Roborock - S9 MaxV Ultra | iRobot - Roomba j9+ |
|---|---|---|
| Lidar | truelead | false |
| Camera navigation | true | true |
| AI obstacle avoidance | true | true |
| Max climb | 40 mmlead | 20 mm |
Autonomy
| Spec | Roborock - S9 MaxV Ultra | iRobot - Roomba j9+ |
|---|---|---|
| Battery life | 180 min | 200 minlead |
| Self-empty base | true | true |
| Self-wash mop | truelead | false |
| Self-dry mop | truelead | false |
| Noise | 65 dBlead | 68 dB |
Frequently asked
Which has stronger suction, S9 MaxV Ultra or Roomba j9+?+
S9 MaxV Ultra delivers 22000 Pa vs 0 Pa.
Do S9 MaxV Ultra or Roomba j9+ mop?+
S9 MaxV Ultra mops; Roomba j9+ vacuums only.
Which has a self-emptying base, S9 MaxV Ultra or Roomba j9+?+
Both ship with a self-emptying base.
Spec-level deep dives
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