Just sharing my experiences. I used Meguiar's Ultimate Wash And Wax . Just apply on the wipers and clean during car wash, normally can last ard a mth or so, plus i believe there is some form form of water repellent from the wax. Had been using it for 3 yrs on my previous BM, so far have not change any wipers . had used rain x before but it will judder and squeak even on a brand new wiper.