My Sharkoon haven't been as silent as I hoped. I tested them out of the case before installing and noticed some noise. In the case they are quieter due to other noise.
Yate Loons are good but I think Silencio_777 has stopped trading?
Noctua seem to be the Silentpcreview current champ.
Edit: looks like Silencio's back after doing a disappearing act for a little while