Why do reviewers recommend Franklin Sensors so often?

The recurring point across r/handyman, r/Tools and r/diynz is that Franklin's 9- and 13-sensor designs show the entire width of a stud at once via a row of LEDs, with no calibration step. Reviewers describe this as faster and more foolproof than single-point electronic finders. The main criticisms are price and a few reports of inconsistent reads on unusual wall assemblies.