The only stud sensor I've used is the "Zircon Studsensor SL" (black
package) and it rarely finds the stud, even when I know where they are.
It's so frustrating, that, for the past few years, I just left it in the
drawer and used the hollow-knock method.
But, today I pulled it out and tried to use it - and again was frustrated
by its lack of repeatability.
Even when I know a stud is there, it is hit or miss with this thing.
Does anyone else have this particular studsensor who can tell me if it's
just mine or if they're all just as worthless?