The Quick Verdict
Get the BenQ LK830ST 4K Short Throw Laser Projector. It's the one of these two where the maker states a 1:1 mode for square impact screens. It's also the only one with a published input-lag figure, 16.7 ms at 1080p 60Hz, and it gives the wider image from the same mounting spot. The Optoma ZW350ST is the call for a 4:3 or 16:9 screen, since Optoma states both of those modes, and it lists at $1,349 against the BenQ's $2,499. That's a $1,150 gap at list.
What They Have in Common
Both are fixed-lens, short-throw laser projectors with 1x optical zoom. Both makers name a golf picture mode, and both state a 4:3 mode alongside 16:9. Neither BenQ nor Optoma says what standard its lumen figure is measured to. Neither publishes a warranty term for these models. The boxes are close in size too: 10.99 x 4.74 x 9.03 in for the BenQ and 10.79 W x 4.49 H x 8.50 D for the Optoma.
Where They Differ
Throw and image size
Image width is the throw distance divided by the throw ratio. The BenQ LK830ST has a 0.496:1 ratio, which gives a 20.2 ft wide image from 10 ft back (10 ft ÷ 0.496). The Optoma ZW350ST has a 0.521:1 ratio, which gives 19.2 ft wide from the same 10 ft (10 ft ÷ 0.521).
Flip it around for a 10 ft wide image. The BenQ sits 5.0 ft from the screen and the Optoma sits 5.2 ft. Both are short-throw by those numbers, and the difference between them is small.
A ratio around 0.5 is the difference between hanging the projector up over the hitting area and hanging it behind you, where you'd be standing between it and the screen. Neither lens zooms, so that single ratio is all you get. Measure from where the lens would sit to the screen before you pick. Optoma states no lens shift and an offset of 115%. BenQ doesn't publish a lens-shift figure for this one.
Screen shape
The BenQ is natively 16:9, and BenQ states 4:3, 16:9, 16:10, 1:1 and 5:4 modes. The Optoma is natively 16:10, and Optoma states 4:3 and 16:9. A square 1:1 mode isn't among Optoma's stated modes. That isn't the same as saying it can't do one, but the BenQ is the only one of the two whose maker lists it.
Resolution, lag and brightness
BenQ lists 3840x2160 and doesn't say how that 4K is produced. Optoma lists 1280x800, which it classes as WXGA.
BenQ publishes 16.7 ms of input lag at 1080p 60Hz. Optoma doesn't publish an input-lag figure for the ZW350ST, so there's no gap to give.
BenQ rates the LK830ST at 4,000 lumens and Optoma rates the ZW350ST at 3,600. Neither maker states the measurement standard, so those two numbers don't measure the same thing, and I won't call either one brighter.
Setup and hardware
The BenQ has 2D keystone with auto vertical correction, ±30 degrees both vertically and horizontally. The Optoma's keystone is ±15° each way.
Optoma rates its laser at 30,000 hours in normal mode, and BenQ rates its laser at 20,000. The Optoma weighs 6.61 lbs, 1.32 lbs lighter than the BenQ's 7.93. The BenQ is a 2025 release and the Optoma a 2023 one.
Who Should Buy Which
Get the BenQ LK830ST 4K Short Throw Laser Projector if:
- Your impact screen is square. BenQ states a 1:1 mode, and Optoma doesn't list one.
- Your screen is 5:4 or 16:10. Those modes are also only on BenQ's stated list.
- You want an input-lag number from the maker before you buy. BenQ gives 16.7 ms at 1080p 60Hz, and Optoma gives none.
- You want 3840x2160 on the spec sheet rather than 1280x800.
- You want the wider image from a given distance: 20.2 ft against 19.2 ft from 10 ft back.
- The mount position leaves the image off-square and you need more correction range. BenQ lists ±30 degrees of keystone each way, against Optoma's ±15°.
Get the Optoma ZW350ST if:
- Your screen is 4:3 or 16:9. Optoma states both modes, and it lists at $1,349.
- The $1,150 gap at list is the deciding number for the build.
- A higher rated light-source life matters. Optoma rates it at 30,000 hours in normal mode.
- The ceiling mount has a weight limit you're watching. The Optoma is 6.61 lbs.
The Bottom Line
Both are short-throw laser projectors with golf modes and nearly the same mounting distance. The BenQ LK830ST lists $1,150 higher at $2,499. For that, it has a stated 1:1 mode, a published 16.7 ms lag figure, 3840x2160 against 1280x800, and wider keystone range. The Optoma ZW350ST makes sense for a 4:3 or 16:9 screen. Call it a hunch, but on a square screen I'd rather have the mode the maker actually lists than hope for one.