I've only put one scope thru a big knock (numerous smaller knocks though). Had a nasty deer season a few years ago, couple inches of snow opening morning, followed by drizzle in the afternoon followed by 10deg temps for the rest of season. Covered every thing in a nasty ice. Slipped and fell more than a few times that season but in one case I had my shotgun in my right hand, slipped, had to use the hand with the gun to TRY to break my fall, came down hard right on the scope. Resighted it in an hour later and it hasn't lost POA since.
Moral of the story....... do some shooting and let the scope tell you if it needs a trip via USPS.