2 reasons:  1)  They don't reduce the noise that much, maybe 4 -5 db lower.  2)  The quality control on most aftermarket propellers isn't good enough.  I saw a video where the mini was vibrating because of the weight inbalance in the propellers.

Which ones did you see?

A J Posted at 7-3 12:14
Which ones did you see?

Front right leg at 2:50 in the video.

trader6777 Posted at 7-3 12:44
Front right leg at 2:50 in the video.

https://youtu.be/A87DR6R-yXI?t=171

I see what you mean - def best to go back to the originals

I don't think there are propellers which can reduce the noise level by 4-5 db. That would mean a 30%-40% noise reduction.

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