I do a little of both. I buy some DD's from the Disney store (or I was before SR) and use those and then I cash out for large amounts 100.00 or more during the special cash outs so that I dont have to carry around as many cards. I have about 105.00 in DD to give the kids for allowance and then take back for safe keeping. I just keep a running total of what everyone has earned and I will split them up for the trip into little wallets for each that I also will carry. My kids are young though so it depends on their age. Mine need to see that they have many DD's to understand that their work is worth something. If your kids are older I would do GC's just because they are so easy to keep track of and they are replacable if you keep your numbers from the back.