We have been living in Vegas for over 10 years and only now finally made it there last spring. I was actually pleasantly surprised by the chocolate quality. I an very picky when it comes to chocolate but this place has very nice selection and very good candies. They are not the cheapest but it's worth it.
Nice addition is their free cactus garden right outside the factory.
Plus you can watch them making candy right from the store (they have glass walls that allow you to see the chocolate making process).
They also sell coffees and teas, which go great together with candy ;)