Mine haven't been able to flip the crock from Walmart so far (knock wood).

As for the answer on the hide and if it's snug enough. The key in this instance is that it's DARK inside, and they feel secure in it. Whichever end they are curled up in, they are feeling touching them on the top and three sides. All my adult females in this tub are set up this way, and all come flying out of those hides on feeding day! LOL