After about 600 rounds on a .300 Weatherby, 2 very wet hunting seasons and hundreds of miles bouncing around in a hard plastic scabbard on my ATV, I have had zero problems with my Zeiss Conquest 3-9X40.
Sounds like the usually Zeiss/Leupold Pissing match.
Let me add some fuel to the fire:
After 30+ years and probably owning close to 100 Leupold scopes in all kinds of configurations never had one let me down. I can' t say that about other scopes I have also owned and some were the so called " High End German Scopes" .