Not a lot of difference with the p3a, since the oem props don't have the winglets, but you get at least a couple more minutes fly time.The difference in noise with the p4 is much more noticeable, somewhere in the region of 3-6 db quieter than the originals. Unfortunately, my first p4+ had the gimbal doa, and only used the oems on that, without doing any measurements. However, my wife, who was walking the dogs at the time, said it was noticeably noisier than the p3a at 120 m. If you can obviously hear the difference, it implies that it is somewhere near -6dbm. I could easily hear it at at 120m with oems, but not with the airmaster props.