my sharpest out-of-the-box knife is my Spyderco S90V Millie which can clearly push-cut newspaper with no pressure at all
however, my FFG Pacific Salt is literally hair-carving sharp (mod done by Romanian knifemaker Matei Campan, you can see some of his work here)
so, what are your sharpest knives and how do you test them?

however, my FFG Pacific Salt is literally hair-carving sharp (mod done by Romanian knifemaker Matei Campan, you can see some of his work here)

so, what are your sharpest knives and how do you test them?