This is a much-discussed topic. Like many divers, I wore one during the first 50-60 dives, it was okay except when heavy current make it pull too hard on my mask. But after looking at the many forums about it and more experienced divers who didn't wear them, I got a foldable and keep it in my pocket. I don't miss it, and have used it only rarely, typically when I got lost, was getting low on air, surfaced, had to swim to the boat, and for some reason wanted to keep an eye on someone or something below while swimming. Otherwise, I can do the swim on my back.