Decidedly Thermalright is very strong right now on the fans. This X-Silent 140 mounted extraction on my case is very convincing. I automatically regulates its speed via SpeedFan Windows. It is very silent on its entire control range, performance is the appointment.
Small thing to note, it needs at least 7V power supply to properly rotate. Which is a relatively high voltage compared to my other fans (often 4 or 5v). However I do not consider this as a default, simply knowing.