The answer — one pick, priced
Get the
Ecovacs Winbot W2S
$10 under your budget
A 25% price cut left it with the $399 flagship's brains — same WIN-SLAM 4.0 navigation, same TruEdge scrubbers — minus only the portable battery station.
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Fit ledger — need → measured evidence
■ The catch — co-equal billing, always
It is tethered to an outlet. There is no battery station, so every pane you clean has to sit within cord reach of a socket. Balcony glass, exterior panes and high-rise windows with no power nearby are simply out of scope for this robot.
Dealbreaker? Runner-up №1 is the same robot with a 110-min battery station ↓
■ Every product has a catch. Verdicts that hide it are how bad buys happen.
Runners-up — if your needs differ
Adjacent verdicts — same method
Traps — this verdict avoids
Round pads miss corners
Every round-pad robot — all the Ecovacs Winbots, the HOBOT-2S — physically cannot reach a pane's 90-degree corners, leaving a 1-2% un-cleaned border you finish by hand. Square pads and scraper blades shrink that border; nothing eliminates it.
The cord is the real ceiling
Only 1 of the 11 robots here runs cordless — the W2 Pro Omni, via its portable battery station. Every other model needs an outlet within cord reach, which rules out most balcony, exterior and high-rise glass.
Maintenance tool, not deep cleaner
Robots leave faint edge streaks on the first pass and are built for routine upkeep, not years-old grime. Use distilled water — tap water leaves mineral streaks — and expect payback only after roughly 3-4 skipped professional cleanings.
Provenance — 7 sources, dated
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