My Take a Look is mounted on the left side of the visor of my helmet. Drilled a small hole in the visor and have the mirror loosely secured with a small ziptie. Before doing that, it would fall off on occasion. I was always able to find it - undamaged.
I'm unable to turn around to look behind me - not possible on most recumbent bikes - and depend on the mirror to keep track of vehicles. Have been using glasses- or helmet-mounted mirrors since at least 1980.