There are a few places within Deco that it makes better sense for using radio buttons over dropdown lists.
The first place is when affiliates sign up for a new website and they have to choose a custom website template. Most affiliates don't even notice that the templates are in a drop-down list, and nearly every new affiliate starts with the default custom store template.
The second place where radio buttons make more sense over a drop down list is on the shipping page. It makes more sense for customer to be able to see all of the shipping methods at once and make a choice from there. Our customers can pick up their orders if they like but most do not because they didnt see that it was a shipping option.