[Perfidiajoe]

SS will out perform alum. that's why you go SS, the prop is behind the bullet of the lower unit, & the skeg. If you hit something hard these will hit first, doing the damage to the lower unit, not the prop. Besides that is why you also have a rubber coupler so the prop will spin, & not break anything else. Of course if you try hard enough you can over come anything. I boat on The Great South Bay, I clam a lot as well as fish off shore. I've run A SS almost exclusively for 12 seasons, same, original lower unit, & there were times it looked as if I were rototilling. Good luck, Joe