Just for info....
The roulette dealer is responsible for and accountable for all roulette chips. In fact they may be reprimanded for missing chips because if they do get returned there is no way of telling what denomination they were purchased for. If a customer brings back lets say five chips a couple hours later and demands $5 each for them, he may have only paid $.50 each. The camera's usually don't help with rapid higher chip stack games like roulette and craps and if they do the dealer is the one who will be "written up". So on the basis of "you didn't hear it here", I would recommend stacks of twenty whenever possible because they will not usually be noticed as soon. And don't forget to tip the dealer......never hurts.