"So, did the stud finder work? Maybe. I’ve tried using it, and am not sure whether I can trust it to detect wires in the wall. Time to go with a name brand."
What the hell. Saying it maybe works as advertised doesn't give you credibility. It's a one button device, you researched how it works, yet you couldn't be bothered to experiment on a few known wires.
I've got one from Bosch (a name brand), and use it to check for steel reinforcements in concrete and power wires in walls (and, rarely, studs). I can't double check the readings non destructively, so I evaluate the device according to whether in the end I hit something or not when drilling.
The readings are imprecise at best, with lots of false positives and possibly some false negatives (no way to know).
The tool is useful, if repeated readings are coupled with domain expertise, common sense and intuition.
If you ask me if the tool, by itself, works, I'll reply "maybe". All I know is that, aided by the tool, I haven't done any damage yet.
I don't think it's the tool's fault though. Rather, it's the combination of non-destructive testing and the limited feedback.
Why do you need to compare the product to another? Why can't you put an extension cord behind a piece of sheetrock and evaluate if there is a false negative? Why can't you try it next to a known electric outlet or light switch?
What the hell. Saying it maybe works as advertised doesn't give you credibility. It's a one button device, you researched how it works, yet you couldn't be bothered to experiment on a few known wires.