Roborock S8 Max Ultra
For buyers who can plumb in the dock and want a hands-off mopping robot that never needs its water tanks touched.
Amazon $599.99$599.99
The Roborock S8 Max Ultra is the better robot vacuum overall, rated 4.1 to 3.9. The Roborock S8 Max Ultra leads on navigation. The iRobot Roomba Plus 515 Combo wins on mopping.
iRobot Roomba Plus 515 Combo
For large, low-furniture homes that want a hot-wash mopping dock and long runtime without paying for camera obstacle avoidance.
Amazon $599.99$599.99
Prices were last checked October 27, 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 Roborock S8 Max Ultra for navigation (LiDAR + 3D light vs LiDAR).
- Choose the iRobot Roomba Plus 515 Combo for mopping (Dual spinning pads, lifts 10 mm, extends to edges vs Vibrating pad, lifts 20 mm, extends to edges).
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 | Roborock S8 Max Ultra | iRobot Roomba Plus 515 Combo |
|---|---|---|
| Overall rating | 4.1/5 | 3.9/5 |
| Cleaning 30% | 63 not yet tested; estimated from 19 tested Roborock robots and the median of the 70 tested robots | 48 not yet tested; estimated from 3 tested iRobot robots and the median of the 70 tested robots |
| Value 25% | 67 $600 | 67 $600 |
| Dock 20% | 100 Self-empties the bin, washes the mop, hot-water mop wash, hot-air mop drying, doses detergent, optional water hookup | 100 Self-empties the bin, washes the mop, hot-water mop wash, hot-air mop drying |
| Navigation 15% | 85 LiDAR + 3D light | 65 LiDAR |
| Mopping 10% | 62 Vibrating pad, lifts 20 mm, extends to edges | 76 Dual spinning pads, lifts 10 mm, extends to edges |
Specifications
| Roborock S8 Max Ultra | iRobot Roomba Plus 515 Combo | |
|---|---|---|
| Vacuum | ||
| Claimed suction | 8,000 Pa | 22,000 Pa |
| Main brush | DuoRoller Riser dual rubber brushes | multi-surface rubber and bristle brush |
| Extending side brush | Yes | - |
| Mopping | ||
| Mop | Vibrating pad, lifts 20 mm, extends to edges | Dual spinning pads, lifts 10 mm, extends to edges |
| Mop lift | 20 mm | 10 mm |
| Leaves mop at dock | No | No |
| Extending mop | Yes | Yes |
| Dock | ||
| Dock | Washes mop + empties | Washes mop + empties |
| Self-empties | Yes | Yes |
| Washes mop | Yes | Yes |
| Hot-water wash | Yes | Yes |
| Hot-air drying | Yes | Yes |
| Detergent dosing | Yes | - |
| Water hookup option | Yes | - |
| Navigation & app | ||
| Navigation | LiDAR + 3D light | LiDAR |
| Obstacle avoidance | 3D structured light (Reactive 3D) | Object sensing (sensor type not given) |
| Voice assistants | Alexa, Google Assistant, Siri Shortcuts | - |
| Build | ||
| Height | 3.8 in (97 mm) | 3.3 in (84 mm) |
| Retracting LiDAR | No | - |
| Battery | 5,200 mAh | 5,200 mAh |
| Run time | - | Up to 4 h 55 min |
| Weight | - | 6.4 lb (2.9 kg) |
| Released | 2024-04 | 2026-07 |