I have never used it in my ski at all. According to the advise of Tony (Dr Honda), it will actually dilute the injected oil, not a good thing. Use only Marine Stabil.
The only way to clean the carbs and filters right is to take it apart. Lots of how to info just do a search. Did mine last year for first time and it was a piece of cake. No product will just clean them without taking them apart. CC