Substitute 1 cup of the following for the semi-sweet chips.
Milk Chocolate; 1/2 cup Chocolate & 1/2 cup Peanut Butter; Peanut Butter; White Chocolate (fyi, can be colored with food coloring); Dark Chocolate; Andes Mint Chips; Butterscotch; Peppermint
These chips can all be found on the baking aisle at your grocery.
If your magic shell hardens, pop it in the microwave on high for 15 seconds and stir. Repeat as necessary.