I've heard of some people who have a tumbler that has some offending wafers that don't retract all the way when the keys are inserted just grind down the wafers that are still protruding until they are flush again or remove them from the tumbler completely... Cheaper than new keys and a new tumbler and moving RFID chips around. A couple have removed all the wafers in the tumbler and just depend on the RFID chips to serve as theft protection. No thief is going to know the wafers have been removed from the tumbler.