Well, the game is very much predetermined. I would love the casino to be random, but it isn't. I look 2-3 times a day now, but it never changes and I am not going to spend 20 gems to get 1 Lab Token in a chest. I won't break the rules and say how you can tell what you can get without actually spending the Gems first, but believe me it can be done.

So, it is predetermined and as the predetermination in the Casino doesn't ever reset, I won't be wasting 20 gems.