In regard to navigational skills:
Several times (on charter boats), I have navigated back to the anchor only to find that the OW class sharing the boat had caused the viz to drop to 5 feet. Sometimes I found the anchor line during my free ascent; sometimes I didn't.
In regard to peer pressure:
Not a problem now that I own my own boat. I'll take it on vacation just because it's there, but I tend to vacation where the viz is good, so I probably won't need it.
In regard to peace of mind:
I usually take 4 divers on my boat. If I know the other buddy team can get back to the boat, I'll think of the Neverlost as extra insurance.