GG3 is slightly different than the newer GG4. Both have a place in window washing, from new construction to residential. GG4 has more degreasing power and is better suited for areas w/hard water. However, I use GG3 often. As a matter of interest, I have been using ABC's Glisten with great results.

If I am focusing on CCU (construction clean-up) I really prefer Unger's Gel as it leaves more suds. To me the suds help me stay on a line with a razor...aslo makes the glass feel more lubed. ABC also makes a product called 'slick' which is a friction reducer, making the glass smoother so-to-speak.

I also use Dawn for the same reason. I am on another forum soley for window cleaners and there has been a debate about GG3 and $ opposed to Dawn for months. Bottom line is preference.