A slot machine/Vegas question

My dad is going to Vegas next week and he loves playing those slots that dispense those big $10 coins that are custom made for the casino. Anyway does anyone know which casinos have such machines? I'm slowly bringing him into the light by the way, last night he called me to let me know that he now understands why I like to play at an empty table and why I kept waking up so early to play. It took him 2 months but he finally got it.