TWP 1500 Series can be used in all 50 states. Both lines are designed for the same uses and perform the same. The decision to use TWP 1500 Series should be based on the need to meet your state regulations.
There are some colors only available in the TWP 1500 Series. If you choose one of these colors you can order them no matter which state you live in. Please note that most retailers stocking TWP 100 Series do not stock TWP 1500 Series.