[masraum]

He doesn't in the short, reveal what he tested and who the winner was. You've got to watch the longer (14min) video for that (unless you have someone that's willing to watch and give you the answer).
It looks like he tested a few of the common/big box cutters like General, Klein, and a $10 pair from Harbor Freight. They all were sub-par. He then did 2 things. 1) he modified a pair by heat treating them and changing the angle of the cutters and 2) he bought some Knipex cutters.

The Knipex cutters were far superior to everything else. The main, visible difference was that the cutters were sharpened to ~50º instead of 45º like all of the rest. The pair that he heat treated (a disassembled set of Kleins) and changed the angle on performed as well as the Knipex after the mods.