If the person does not know how to fight even a soccer kick with some hard shoes will take their leg out.
I do full contact karate and Muay Thai.
The way I see it that in self defense you do not really want to use kicks much. You have more control with fists and in the clinch.
The kicks that are affective are low kicks and thai style is the best for them. Mid or high kicks I would do with shoes.
You can easily shin kick someone out who doesn't know anything. Depending on the shoe it is overall stronger than the shin in my opinion.
If you are wearing sandals I would use shins. If you are wearing tennis or running shoes then I would use the shoe for mid kicks. High kicks are risky but they better with the shoe. If you have steal toe shoes then yeah the shoes.
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