Between the X40 Ultra and S8 Pro Ultra, the X40 Ultra comes out ahead in suction and water tank, while the S8 Pro Ultra wins on several specs. Overall, the X40 Ultra scores 70.7 and the S8 Pro Ultra scores 57.7 on our Mars Score.
Which should you buy?
The X40 Ultra is the clear pick on raw spec strength, leading by 13.0 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 X40 Ultra if you care most about suction and water tank. The biggest gaps in its favor are suction, water tank, battery life, among others.
The S8 Pro Ultra similarly doesn't carry a headline advantage on the popular specs — look at the full table for category-specific deltas.
Both ship with comparable mopping, lidar, self-empty base, so those specs don't separate the two — focus on the differences below.
Bottom line: the X40 Ultra is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why Dreame - X40 Ultra wins
- ▲Suction — 100.00% more. 12000 Pa vs 6000 Pa.
- ▲Water tank — 50.00% more. 270 ml vs 180 ml.
- ▲Battery life — 16.67% more. 210 min vs 180 min.
- ▲Noise — 2.00 dB less. 65 vs 67.
Why Roborock - S8 Pro Ultra wins
- No decisive advantages.
Spec comparison
Cleaning
| Spec | Dreame - X40 Ultra | Roborock - S8 Pro Ultra |
|---|---|---|
| Suction | 12000 Palead | 6000 Pa |
| Mopping | true | true |
| Water tank | 270 mllead | 180 ml |
| Dustbin | 350 ml | 400 mllead |
| Carpet detection | true | true |
Navigation
| Spec | Dreame - X40 Ultra | Roborock - S8 Pro Ultra |
|---|---|---|
| Lidar | true | true |
| Camera navigation | true | true |
| AI obstacle avoidance | true | true |
| Max climb | 60 mmlead | 20 mm |
Autonomy
| Spec | Dreame - X40 Ultra | Roborock - S8 Pro Ultra |
|---|---|---|
| Battery life | 210 minlead | 180 min |
| Self-empty base | true | true |
| Self-wash mop | true | true |
| Self-dry mop | true | true |
| Noise | 65 dBlead | 67 dB |
Frequently asked
Which has stronger suction, X40 Ultra or S8 Pro Ultra?+
X40 Ultra delivers 12000 Pa vs 6000 Pa.
Do X40 Ultra or S8 Pro Ultra mop?+
Both can mop.
Which has a self-emptying base, X40 Ultra or S8 Pro Ultra?+
Both ship with a self-emptying base.
Spec-level deep dives
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