Until I built a FliteTest plane, I never broke a prop. I've owned 3 Horizon Hobby planes, and I've never broke a prop on any of them (I did break a prop shaft once though). But then I entered the world of DIY FT planes. I was using the props supplied in the FT Power Packs and I was braking them very quickly. I remember breaking 3 in one day. I was not happy. The amount of money I spend on props mounts up and it's money I didn't want to spend. Then I found these props. I tried them and love them. They are much, much stronger. True, they break, but it takes a very hard crash to brake them. They are also bigger, meaning they provide more punch. Buy them and try them. You'll see and feel the difference.