Silence has a price... but it's golden!
The price may seem high, but the results are impressive!
I took 5 of them to replace the Pure Wings 2 DC in my Pure Base 600 case, and it's now absolutely quiet: 30% at rest, 50% at 45°C and 70% at 60°C. Even when I'm playing games, the quietness means I can enjoy the game.
Even at 30% with 5 fans, my speakers, switched on without sound, make more noise. A joy, and above all a good investment.
For my next set-up, I'll be taking a Be Quiet! case and replacing it with the higher range (Silent Wings Pro) to benefit from the same quietness, but even better cooling with a Dark Rock Pro Elite (and avoid an AIO).