Just a quick test with the new Low Noise Props for the DJI Mavic Pro.
I compared the original ones with the new ones.
My iPhone 6S-plus was used to check the dB's, at the same distance. So this is not pro dB meter. But the difference is substantial.
In hover mode is't about 20dB less noisy. Not bad at all.
I did not test the performance. So there might be a difference is that.