My experience is that sometimes it is fast, sometimes it is slow. Because of the vriable timing, I can't tell when it is safe to close my lid to avoid the dreaded hard-lock that I often get when I close my lid as it enters sleep mode. I either have to close it immediately or wait for it to finish completely and the keyboard backlighting goes out before closing it. I have my lid sensor set to "do nothing" so that I can close it and move around without interrupting downloads or live streams. It would be fine if it was still set to trigger sleep by closing it, but I've never understood how people tolerate that default setting. For some strange reason there are actually TWO sensors and at least one is a magnetic relay switch.