Chops is not an a la carte restaurant. Your UDP will get you anything on the Chops menu that doesn't have a price. If an item has a price (Lobster $21), you will eat everything else for free, and pay $21 for the lobster.
Izumi is a la carte. UDP gets $20 credit at Izumi. If you order $25 of food, you will pay $5.
Hibachi has a $10 upcharge when you have UDP. You pay $10 and all other items are free.