Speaking as someone who rides with bike shoes and platform pedals, I can say they make a huge difference. When I wear street shoes they flex and I get a pain in my right ankle because my foot is twisting outward due to the flex. The pedals I have have lots of sharp teeth on them, and the shoes I have are closer to a MTB shoes and not a slick Sidi or something, and therefore I don't slip. I used to use a clipless system but I'm not a true believer when it comes to clipless, which I've used and don't use anymore. The ability to put your foot down and up as much as you want is too useful to me. I don't consider a system where you fall all the time to be safer.