My laser level was off by 1/4 inch and I found out why in my garage last night
I was hanging cabinets in my kitchen and kept noticing things didn't line up. Checked the bubble on my old Stanley level and it looked fine. Then I set my laser level on a countertop I knew was dead flat and shone it across the room. The line was tilted by almost a quarter inch over 15 feet. Turns out the internal pendulum on that cheap Bosch model I bought at Lowe's for 60 bucks got jammed with dust after sitting in my tool bag for a year. Anyone else ever have a tool gradually drift off and not notice until you're already done with a job?
Twenty bucks says that cheap Bosch pendulum is still sitting in your tool bag gathering more dust too. Nothing like finding out your "helpful assistant" is actually a lying piece of plastic halfway through a cabinet install.
Does anyone else wonder if @the_cora had bad luck with that particular Bosch model, or if it's the whole concept of pendulum stud finders that's the problem? I've been using a basic Zircon for years and it's never given me false readings, but I've heard enough people complain about those self-leveling ones to think maybe they just don't work well on anything but perfect drywall. The extra moving parts seem like they'd introduce more chances for error, not less.
Haven't you found that even the basic Zircon can act up if you've got old textured walls or something behind the drywall that's not a stud? I've had mine give false positives near pipes and old metal conduit.