Review on VIVREAL 4 In 1 Stud Finder Wall Scanner With LCD Display - Center Finding Beam Finder And Sound Warning For Wood, AC Wire, And Metal Studs (Black/Silver) by Adam Allard

I've only used for studs. I find that the readings are a little confusing when finding the edge. The center mark seems to be accurate however the edge mark's are off. The edge marks sometimes go on for as much as a quarter inch but usually about an 8th. Making it seem like the stud is 2in thick when it's actually 1.5in.I use the below to accurately measure a 1.5in stud1) measure from left to right2) move to right, continuing to move even though the arrow and edge bar appear. Stop and mark wall when the edge bar disappears.3) continue to move and mark center.4) measure from left to right5) find right edge using steps from 2.6) verify center.This usually results in a stud width of 1.5in sometimes an 8th smallerUsually i dont care for the edge so I mark the center from each direction and drill, nail or screw in between those marks.Note: center mark had a little give too. This I find is usually less than an 8th of an inch. Also, sometimes reading the same stud edge can give inconsistent readings.Even with the above, I will not be returning. It works well enough for my needs and the AC wire warning had already saved me. You can even track the wire for horizontal or vertical runs.All in all. I will recommend because the reading errors may be caused by imperfect studs, drywall screws or something else.