They have parts like PMW3360 in a mouse clearly intended for office use, judging by its shape; no wonder it's expensive. This is a sensor designed for extremely

They have parts like PMW3360 in a mouse clearly intended for office use, judging by its shape; no wonder it's expensive. This is a sensor designed for extremely fast movements in games (faster than punches in most martial arts). It's not the latest and hottest model, but you won't be able to tell the difference from a cheap sensor during normal use.