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Both Tom and Tim have more prop expertise by far than I do. I will say this though. There is no reason at all to use an aluminum propeller.
In the good old days Yamaha sold all the motors above 30hp with stainless props. When I replaced my 1985 70hp 2-stroke with the same motor in 2007 it came with aluminum. I took the 22 year old stainless off the old motor which I sold. I gave the buyer the new aluminum.

By the way I run in shallow water constantly and run in sand or mud almost every trip at some point.