The razor is better than even an iron sword, because knives are way overpowered in the game. I was destroying everything except Fuling berserkers and maybe lox when I used knives.

Swords require more timing and strategy, whereas knife attacks can be spammed fairly freely as long as you've no more than 1 health food (so 2 stamina ones or stamina and balanced).

The knife secondary attack has range, eliminating the minimal reach drawback.