Eprops are designed from the ground up by very smart people versed in fluid dynamic and using some very trick software. They just dont copy and remix old designs. You have to remember that the Eprop for Rotax engines was specifically designed for the engine that has a gearbox. NOT a direct drive although later this year they will release their new prop for the Jabiru series of engines which is a 2 blade. You can of course get a 2 blade for a rotax but that is a waste because again it was designed for a gearbox engine. It also helps that it is the lightest propellor you can get with the latest materials. Everyone also notices the vast difference when starting and stopping the engine...no more big clunks..The blades are not wide like all other props..this reduces the drag of the propellor. One thing to remember of course is that reduced drag will affect your landing approach. Every single customer who has bought a Eprop from me has been super happy and every single one has had a dramatic increase in cruise speed. Also they all cant believe how smooth they are..they are a huge level above anything even with the best dynamic balance you can do on a normal prop. I have sold over 70 props now and in fact another 2 are on order this week. If you set them up as per the instructions they tell you then you will get the performance. If you listen to the "old guard" you will NOT get the performace. The designers know what they are doing.
One of the first few props I sold was for a A22 foxbat..he got 8kts increase in cruise..he used to love is Warp Drive props...he sold all 3 he had after using the Eprop. I dont want this to be taken as a sales pitch. It isnt. Its just information to chew on but the best recommendation is from the people that use them. I dont have to have any sales pitch..they sell themselves.