If you put a heavy duty shaft zinc, you could have about 5 times the protection. You can still have the Max Prop conical zinc. It will last longer, I suspect.
You are comparing over 3 pounds vs 0.6 pounds. If you put 2 heavy duty shaft zincs ...
Many years ago our Pearson 35 lost its prop due to electrolysis in a marina. I've been careful since then ;^)))