I'm an electrician. I've had these for about a year now, and they blow any ordinary diagonal cutters totally away. They have a compound joint, which effectively doubles their leverage. They are rated for cutting steel, so copper is like butter to them. I have small hands, so seeing me cut through 8/3 for ranges with an ordinary pair was a spectacle. These Irwin's cut through 8/3 in one cut, easily, one handed...well, they could, except they don't open nearly far enough to cut the whole cable. So they can cut 8/3 in two cuts more easily than someone cutting 14/2 with a regular pair. Every electrician whom I've let test them out have been impressed and did not expect them to cut so effortlessly. Works great cutting through MC too.