Research after research show that site visitors act better on radio buttons than on dropdown boxes. It is also clear why: with radio buttons you see all the options in a glance and the option of choice is easily checked.
People prefer “Color: O red O green O blue” to “Color: [Please select an option]”
Unforunately, configurable products require dropdown-boxes. That is not a problem in the back-end. But in the front end it is bad for clarity, user-friendliness and most importantly, conversion and sales.
It would be great if products could be configured using radio buttons.