I cash in every time and the secret is that you play when the tables are busy and others are betting lots of chips. When the last number falls and the dealer pays the bets immediately tell him that you want to cash in. He normally cashes you in before he sorts all of the chips. By the time the chips are sorted you are long gone. the best bet is those few table that have automatic chip sorters. I don't think they ever know how many chips are in the machine.