Wow, replacement complete blades are sure much quieter than my old worn ones. Kind of expensive tho -- prices varied widely so shop it out. Also there are some Bosch parts available which are not exactly like the original OEMs, that have air dams one side. I,m supposing the air dams help at high driving speeds. I did not buy the standard Bosch ones, but got the OEMs which are made exactly like the factory wipers and do a nice job. I think that 12 years wear allowed more slack at all the pins and made the noise (a loud clack at direction change) I was getting before replacement. If you love "quiet" go for new blades.
DanielW