The catch
Sunseeker S4
The LiDAR advantage may not save it, because a smaller area rating and grass exclusions can disqualify it.
Side by side
Sunseeker S4 vs Sunseeker X3 Plus: S4 needs no antenna in shade but excludes Zoysia and St. Augustine
Quick verdict
S4 fits a compatible shaded lawn below quarter acre where an RTK antenna would be awkward to install. X3 Plus fits a mostly open lawn between quarter and three-tenths acre. Check the grass type first, because Sunseeker’s S4 guidance excludes Zoysia and St. Augustine.
Before you buy
Why, and what it costs you
A slightly bigger lawn can take the newer navigation option off the table
A 0.28-acre lawn sits about 12 percent over S4’s rating and under X3 Plus’s limit. Navigation that copes better with tree cover does not get around the area limit. For that lawn, X3 Plus makes sense only if RTK placement works out. Otherwise look at a larger LiDAR mower.
Where this comes from
Sunseeker S4: 0.25-acre rating. 0.28 / 0.25 - 1 = 12 percent. Sunseeker X3 Plus: 0.3-acre rating with RTK installation.
The catch
Sunseeker X3 Plus
Flexibility suffers from RTK placement, daytime-only operation and a lower slope limit.
Sunseeker S4
- Why pick it
- Dense tree cover shades a lawn below quarter acre
- LiDAR with no RTK antenna is what you want
- The catch
- The LiDAR advantage may not save it, because a smaller area rating and grass exclusions can disqualify it.
Sunseeker X3 Plus
- Why pick it
- Your lawn is over quarter acre but under 0.3 acre
- Installing RTK under clear sky is practical
- The catch
- Flexibility suffers from RTK placement, daytime-only operation and a lower slope limit.
We may earn a commission from qualifying Amazon purchases. How we make money
What this page compares
Sunseeker S4 vs X3 Plus for a small yard. Weigh tree cover, grass exclusions, slopes and the daytime schedule before you settle on a navigation system.
Which one fits
Pick the situations that sound like you
Compatible grass on a shaded 0.2-acre lawn
The S4 needs no RTK antenna. Still check geometry and boundaries.
- Sunseeker S4
- Better fit
- Sunseeker X3 Plus
- Depends
A wide-open 0.28-acre lawn
X3 Plus stays inside its rating, while the S4 goes past its limit.
- Sunseeker S4
- Not suitable
- Sunseeker X3 Plus
- Better fit
An interior bank at 35 percent
The S4 clears the headline slope threshold, but only when turf and installation work out too.
- Sunseeker S4
- Depends
- Sunseeker X3 Plus
- Not suitable
A Zoysia lawn
The S4 states its exclusion outright. Confirm turf suitability for the X3 Plus rather than assume it.
- Sunseeker S4
- Not suitable
- Sunseeker X3 Plus
- Depends
In practice
Differences you will notice
A slightly bigger lawn can take the newer navigation option off the table
A 0.28-acre lawn sits about 12 percent over S4’s rating and under X3 Plus’s limit. Navigation that copes better with tree cover does not get around the area limit. For that lawn, X3 Plus makes sense only if RTK placement works out. Otherwise look at a larger LiDAR mower.
How we worked this out
Sunseeker S4: 0.25-acre rating. 0.28 / 0.25 - 1 = 12 percent. Sunseeker X3 Plus: 0.3-acre rating with RTK installation.
A two-hour free-lawn window shifts how the cycle plays out
From a full charge, the S4’s stated cycle stops after about 90 minutes, while X3 Plus claims up to 120 minutes before it needs to recharge. That gap counts when mowing has to be done before children use the lawn. Still, neither claim promises the yard will be finished.
How we worked this out
Sunseeker S4: 90-minute mowing claim, 80-minute charging claim. Sunseeker X3 Plus: 120-minute mowing claim, 90-minute charging claim. Daytime operation required.
Passing on slope does not mean passing on grass
For a 35 percent interior bank, the S4 is the candidate with its 42 percent slope rating, since X3 Plus stops at 30 percent. The S4’s explicit grass exclusions still apply, though. A slope number that fits cannot make an excluded turf type a recommendation.
How we worked this out
Sunseeker S4: 42 percent interior slope claim and named grass exclusions. Sunseeker X3 Plus: 30 percent interior slope claim. No exemption from turf checks inferred.
Plug in your numbers
Can either mower handle your yard?
This checks hard limits only. Personal preferences are left out of the math.
Sunseeker S4
Works with your numbersIts rating covers 0.25 acre and 42% grades inside the boundary, with no wire to lay. You entered 0.25 acre and a 20% grade.
Sunseeker X3 Plus
Works with your numbersIts rating covers 0.3 acre and 30% grades inside the boundary, with no wire to lay. You entered 0.25 acre and a 20% grade.
The area check uses the published maximum with no reserve added. When a systematic mowing rating is shown, the mower has to follow that pattern to reach the maximum area. Slopes at the boundary can have a lower limit than the interior. You still need to check trees, gates and separate zones.
Option A
Sunseeker, S4
S4
This quarter-acre LiDAR mower needs no RTK antenna, but it comes with significant grass-type and boundary restrictions you should check before choosing it.
- Best for
- Dense tree cover shades a lawn below quarter acre
Facts we checked
- Rated lawn size: 0.25 acre
- Navigation: LiDAR and vision, no RTK antenna
- Interior slope limit: 42 percent
- Mow and charge claims: 90 minutes mowing, 80 charging
Option B
Sunseeker, X3 Plus
X3 Plus
This RTK and vision mower suits a mostly open three-tenths-acre lawn. It mows during the day and has a 3.2-inch cutting ceiling.
- Best for
- Your lawn is over quarter acre but under 0.3 acre
Facts we checked
- Rated lawn size: 0.3 acre
- Navigation: RTK and vision
- Interior slope limit: 30 percent
- Mow and charge claims: 120 minutes mowing, 90 charging
Spec by spec
Where they really differ
| Spec | Sunseeker S4 | Sunseeker X3 Plus | In practice |
|---|---|---|---|
| Rated lawn size | 0.25 acre | 0.3 acre | The area rating is not larger on the higher navigation tier. |
| Navigation | LiDAR and vision, no RTK antenna | RTK and vision | The area gap can matter less than tree cover and where the antenna goes. |
| Interior slope limit | 42 percent | 30 percent | Given a 35 percent interior bank, the choice shifts, provided every other installation limit is met. |
| Mow and charge claims | 90 minutes mowing, 80 charging | 120 minutes mowing, 90 charging | These are figures for separate cycles. None guarantees how long the whole yard takes. |
| Grass and daylight | US guidance excludes Zoysia and St. Augustine | FAQ specifies daytime operation | Make sure the turf suits the mower, and note when people and pets are off the lawn. |
Trade-offs
What each pick costs you
With Sunseeker S4
- A 30-inch gate is too narrow for the 80 cm minimum passage.
With Sunseeker X3 Plus
- Sunseeker’s S4 has a higher slope limit than the 30 percent here.
Change of plan
When the answer changes
Dense tree cover shades a lawn below quarter acre
Go with Sunseeker S4. LiDAR with no RTK antenna is what you want
Your lawn is over quarter acre but under 0.3 acre
Go with Sunseeker X3 Plus. Installing RTK under clear sky is practical
By the numbers
What the data shows
What we found across the robotic lawn mowers we compare, plus the checked facts behind each finding.
Show the facts and the math
| Product | Needs it meets | Facts we checked | Sources |
|---|---|---|---|
| Sunseeker S4 |
|
|
|
| Sunseeker X3 Plus |
|
|
|
Ready to buy
See today’s price and what owners say
Open either model on Amazon for the current price, customer reviews and delivery options.
Sunseeker S4
Dense tree cover shades a lawn below quarter acre
See price & reviews on AmazonSunseeker X3 Plus
Your lawn is over quarter acre but under 0.3 acre
See price & reviews on AmazonEach link opens in a new tab.
We may earn a commission from qualifying Amazon purchases. How we make money