Dreame X40 Ultra
Dreame’s 2024 flagship, now hard to find new; worth it only at a deep discount, as the X50 and L-series robots clean better.
AmazonThe Dreame X40 Ultra is the better robot vacuum overall, rated 3.8 to 3.5. The Dreame X40 Ultra leads on mopping. The Roborock Qrevo Slim wins on dock.
Roborock Qrevo Slim
Only worth it deeply discounted for very low furniture; newer slim Roborocks clean better for less.
Amazon $1,399.99$1,399.99
Prices were last checked October 26, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the Dreame X40 Ultra for mopping (Dual spinning pads, leaves its mop at the dock for carpet, extends to edges vs Dual spinning pads, lifts 10 mm, extends to edges).
- Choose the Roborock Qrevo Slim for dock (Self-empties the bin, washes the mop, hot-water mop wash, hot-air mop drying, doses detergent, optional water hookup vs Self-empties the bin, washes the mop, hot-water mop wash, hot-air mop drying, doses detergent).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every self-cleaning dock robot vacuum; a clear win is highlighted. How we rank explains each one.
| Factor weight | Dreame X40 Ultra | Roborock Qrevo Slim |
|---|---|---|
| Overall rating | 3.8/5 | 3.5/5 |
| Cleaning 30% | 37 measured 80% of sand from carpet, 75.5% of pet hair, some hair tangled (0.8) | 40 measured 76% of sand from carpet, 80% of pet hair, some hair tangled (0.2) |
| Value 25% | 50 no current price (neutral score used) | 15 $1,400 |
| Dock 20% | 90 Self-empties the bin, washes the mop, hot-water mop wash, hot-air mop drying, doses detergent | 100 Self-empties the bin, washes the mop, hot-water mop wash, hot-air mop drying, doses detergent, optional water hookup |
| Navigation 15% | 100 LiDAR + camera | 100 LiDAR + camera |
| Mopping 10% | 86 Dual spinning pads, leaves its mop at the dock for carpet, extends to edges | 76 Dual spinning pads, lifts 10 mm, extends to edges |
Independent tests
Dreame X40 Ultra
| Tested by | Carpet deep clean | Pet hair | Hair tangle (0 = none) | Area per charge | Conditions |
|---|---|---|---|---|---|
| Vacuum Wars | 80% | 75.5% | 0.8 | 1,287 sq ft | Embedded sand in medium-pile carpet; flattened 2.5 in pet hair on carpet, two runs; 7 in hair tangle on hard floor (0 = none wrapped). |
Roborock Qrevo Slim
| Tested by | Carpet deep clean | Pet hair | Hair tangle (0 = none) | Area per charge | Conditions |
|---|---|---|---|---|---|
| Vacuum Wars | 76% | 80% | 0.2 | 1,160 sq ft | Embedded sand in medium-pile carpet; flattened 2.5 in pet hair on carpet, two runs; 7 in hair tangle on hard floor (0 = none wrapped). |
Specifications
| Dreame X40 Ultra | Roborock Qrevo Slim | |
|---|---|---|
| Vacuum | ||
| Claimed suction | 12,000 Pa | 11,000 Pa |
| Main brush | Liftable rubber brush (TriCut Brush 2.0 sold separately) | DuoRoller Riser all-rubber brushes |
| Dustbin | 300 mL | 220 mL |
| Extending side brush | Yes | Yes |
| Mopping | ||
| Mop | Dual spinning pads, leaves its mop at the dock for carpet, extends to edges | Dual spinning pads, lifts 10 mm, extends to edges |
| Mop lift | 10.5 mm | 10 mm |
| Leaves mop at dock | Yes | No |
| Extending mop | Yes | Yes |
| Water tank | 80 mL | 72 mL |
| Dock | ||
| Dock | Washes mop + empties | Washes mop + empties |
| Self-empties | Yes | Yes |
| Dust bag | 3.2 L | - |
| Washes mop | Yes | Yes |
| Hot-water wash | Yes | Yes |
| Hot-air drying | Yes | Yes |
| Detergent dosing | Yes | Yes |
| Water hookup option | No | Yes |
| Clean water tank | 4.5 L | - |
| Navigation & app | ||
| Navigation | LiDAR + camera | LiDAR + camera |
| Obstacle avoidance | RGB camera plus 3D structured light, recognises 120 object types | 3D sensors and RGB camera |
| Climbs thresholds | 22 mm | 20 mm |
| Matter | - | Yes |
| Voice assistants | Alexa, Siri, Google Home | Alexa, Google Assistant, Siri |
| Build | ||
| Height | - | 3.2 in (82 mm) |
| Retracting LiDAR | - | No |
| Battery | 6,400 mAh | 5,200 mAh |
| Run time | - | Up to 3 h |
| Weight | - | 9 lb (4.1 kg) |
| Warranty | 3 years | 1 year |
| Released | 2024-04 | 2024-09 |