I love boiled radishes for a wide variety of reasons. The crispness of the skin is a nice counterpoint to the cool, fresh taste they have. They also come in a wide variety of flavors, unlike most dried root vegetables.
The ones that are best cooked this way are the ones that are best cooked in a microwave and steamed. Steaming the potatoes, cauliflower, and carrots helps get the texture of the radishes.