Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Dreame - L40 Ultra | Roborock - S9 MaxV Ultra |
|---|---|---|
| Suction | 11000 Pa | 22000 Pa |
| Water tank | 260 ml | 300 ml |
| Battery life | 200 min | 180 min |
Between the L40 Ultra and S9 MaxV Ultra, the L40 Ultra comes out ahead in battery life, while the S9 MaxV Ultra wins on suction / water tank. Overall, the L40 Ultra scores 82.9 and the S9 MaxV Ultra scores 88 on our Mars Score.
Which should you buy?
The S9 MaxV Ultra edges ahead on the Mars Score (82.9 vs 88), but the 5.1-point gap is small enough that the right pick comes down to which spec advantages matter to you.
Pick the L40 Ultra if you care most about battery life. The biggest gaps in its favor are battery life. The single most decisive one: Battery life — 11.11% more. 200 min vs 180 min.
Pick the S9 MaxV Ultra if you care most about suction / water tank. Its strongest claims are suction, water tank. The single most decisive one: Suction — 100.00% more. 22000 Pa vs 11000 Pa.
Both ship with comparable mopping, lidar, self-empty base, so those specs do not 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.
Which should you buy: Dreame - L40 Ultra or Roborock - S9 MaxV Ultra?
Roborock - S9 MaxV Ultra leads the current Mars Score by 5.1 points.The more useful decision is the trade-off behind that result: compare suction, battery life against the way you will actually use the product.
Choose Dreame - L40 Ultra if…
Dreame - L40 Ultra has the measurable edge on battery life min.
Choose Roborock - S9 MaxV Ultra if…
Roborock - S9 MaxV Ultra has the measurable edge on suction pa, water tank capacity ml.
This is a structured comparison of the published catalog values. It is not a claim of identical real-world performance across every workload; use the linked spec drill-downs and methodology page to inspect the inputs.
Why Dreame - L40 Ultra wins
- ▲Battery life — 11.11% more. 200 min vs 180 min.
Why Roborock - S9 MaxV Ultra wins
- ▲Suction — 100.00% more. 22000 Pa vs 11000 Pa.
- ▲Water tank — 15.38% more. 300 ml vs 260 ml.
Spec comparison
Cleaning
| Spec | Dreame - L40 Ultra | Roborock - S9 MaxV Ultra |
|---|---|---|
| Suction | 11000 Pa | 22000 Palead |
| Mopping | true | true |
| Water tank | 260 ml | 300 mllead |
| Dustbin | 320 ml | 350 mllead |
| Carpet detection | true | true |
Navigation
| Spec | Dreame - L40 Ultra | Roborock - S9 MaxV Ultra |
|---|---|---|
| Lidar | true | true |
| Camera navigation | true | true |
| AI obstacle avoidance | true | true |
| Max climb | 40 mm | 40 mm |
Autonomy
| Spec | Dreame - L40 Ultra | Roborock - S9 MaxV Ultra |
|---|---|---|
| Battery life | 200 minlead | 180 min |
| Self-empty base | true | true |
| Self-wash mop | true | true |
| Self-dry mop | true | true |
| Noise | 65 dB | 65 dB |
Frequently asked
Which has stronger suction, L40 Ultra or S9 MaxV Ultra?+
S9 MaxV Ultra delivers 22000 Pa vs 11000 Pa.
Do L40 Ultra or S9 MaxV Ultra mop?+
Both can mop.
Which has a self-emptying base, L40 Ultra or S9 MaxV Ultra?+
Both ship with a self-emptying base.