on my car when it was new I have tried vinegar with no joy.it works for so long but not very long.
I have also tried the everlasting( five blades in one) from the pound shop. thay lasted about two weeks utter sh*&^t
I have tried many things over the years as I am well fussy when it comes to windscreens, the only thing that seems to work for me is by using a very very good screen cleaner, I use Autoglym and have to say since using this I never have a problem with chattering also cleans extremely well ,I use double the amount they recommend.