Ten years ago - after playing every weekend for about 3 months... I took my first neck-shot. I became winded, didn't know what to do...and it knocked me on my ass. Literally. I sat down in this shredded rubber pit of a field...caught my breath and thought "wow..."
I promptly went to the counter of my pro shop, and picked up a neck guard. I wore it that weekend. The second one to the throat hurt, but it didn't mark. (yes..2 to the throat in 1 weekend).
But...honestly - I've only worn the damn thing that day, and probably a hand full of other days since. The first one to the neck is like a first punch to the jaw. It hurts...bad... and every one thereafter isn't so terrible. I don't wear it because I find it makes it harder to breathe...and that's already inhibited by the mask.