just started using this stuff in last couple months and have now gotta agree with the other wc'ers on here... Ive dumped fairy liquid and vinegar & squeegee off, GG4 is the way forward if its mixed right! took me a few goes to get it right but am well pleased with the results now

Fairy gets them clean and is ok to start with but if you want pro looking work and less detailing then get some gg4.