How do you know what size spinner to run? I am replacing my 10x4 3 blade Evo PTS prop with the common MAS 2 blade 10x6, for starters. I used a 2", which was very close to what was OEM. I hear people saying run 2.5 to 2.75 spinners...............what determines this?

Will the 10x6 load the motor harder than the 10x4 3 blade? I still want docile handling for the wife, but dont want to overev the motor. The two blades seem to be the best option.