On one of my trips to RSA I had one on to check zero. The PH suggested that I leave it on for the hunt. First animal was a big Kudu. He forgot about the brake. The muzzle blast distracted him so much he asked me where the bull was. He lost track of it in his bino's. I told him it went straight down. He said chamber another round. I told him that I had already done that....... I took it off that night for the rest of the hunt.
Like mentioned most PH's don't care for them. Nor the trackers.
Bruce