Quick static comparison of regular twin-blade propellers vs the new tri-blade propellers (from Banggood) on a CX-10. While less efficient than the two blade props, the tri-blade props are quite a bit quieter and have more of a whisper or wind sound compared to the loud wine of the twin-blads. I attempted to capture the difference in this video, but unfortunately my camera's high sound sensitivity and auto-gain tends to equalize volume variation. In person, the difference in is quite noticeable, especially at the lower RPM range typical of average flying and hover. Not as much at full throttle, but you can hear the difference in sound quality and pitch.
As for efficiency, on my CX-10 from a full charge of 4.22v to an LVC (not LVW) of 3.35v, the regular twin-blade props went almost exactly 5 minutes; tri-blades delivered 3:55. So there's about a 20% efficiency loss with the tri-blades.
