5-6 choices: Radio button or drop down?

I'm redesigning a PMS (Property Management System) and this is a screen from the set up of a hotel. Now there are radio buttons in all of the categories/tabs. I know that there is a 'rule' that if the choices are less than 6 it is better to use radio button and show all the choices instead of a dropdown button. Although there are more than 5 categories/tabs that you need to choose one choice and I don't know what is the best solution for my problem. Do you think I should stay with the radio buttons or a drop down button? Do you have any other ideas?