Benefits of Stainless Steel Propellers
Stainless steel is a stiff material, which means it transmits power to the water more efficiently than NiBrAl, the other material used to construct watersports propellers. That stiffness makes stainless steel the material of choice for use in applications where the highest maximum speed is the ultimate goal.
Disadvantages of Stainless Steel Propellers
Stainless steel's strength is also its primary disadvantage; the stiffer blades are also more efficient at transferring energy up into the drivetrain of the boat when an impact occurs. That means an incident where damage would normally be limited to the prop alone when running a NiBrAl propeller can wreak havoc throughout the rest of the drivetrain, causing significantly more damage.
Why Stainless Steel isn't Used in Watersports Propellers
The higher top speed of a stainless steel prop offers little to no benefit for wakesurfing, wakeboarding and waterskiing. Additionally, stainless steel is too hard to be machined affordably, so stainless propellers must be cast, which further reduces the performance of the propeller compared to modern CNC machined models.
Those reasons combined with the increased likelihood for damage to the rest of the boat as a result of an impact has resulted in the highest performing propellers in the industry being produced exclusively from NiBrAl alloy.
If you want the best performance for your inboard boat, your want a NiBrAl propeller from Acme Marine Propellers
or OJ Propellers