Roborock RockMow X115H vs Roborock RockMow X120H

The Roborock RockMow X115H on value, because it costs less, runs longer, supports Alexa and Google Home and has a published three-year warranty. The Roborock RockMow X120H is the better mower for a shaded half-acre, where its 360 degree 3D LiDAR navigation needs no antenna and no satellite fix.

How they navigate. The Roborock RockMow X115H uses full-band RTK plus four cameras and needs its reference station in the open, while the Roborock RockMow X120H uses a 360 degree 3D LiDAR and dual cameras with no RTK and no antenna. That makes the X120H the stronger choice under trees.

Neither needs a perimeter wire. Both map the lawn digitally with no-go zones and multi-zone maps. The difference is positioning: the Roborock RockMow X115H uses RTK with cameras, and the Roborock RockMow X120H uses LiDAR with cameras.

They are identical on terrain: both are all-wheel drive, both are rated for an 80% slope and both clear obstacles up to 3.1 in. The choice between them is about navigation and smart home support, not climbing ability.

Owners of a mostly open lawn up to about three eighths of an acre who want a capable 4WD mower with voice control, a longer runtime and a proper warranty, and who have space to mount the RTK reference station.

Anyone with a half-acre garden hemmed in by trees, walls or buildings where RTK loses its fix, who is happy to control everything from the Roborock app and does not need Alexa, Google Home or Home Assistant.