I remember training someone with the Aplha 40 and the 3-blade actually governed the high speed and kept it from going too fast. Perfect for training . I think the 3-blade was an odd size like 10.75X 4 . Probably won't find that in a Master Airscrew but a 10X5 3-blade should be fine and yes the MA prop will last a lot longer than the stock H9 prop even if it's twice the price.