nice write up Sean! For me the biggest advantage of using ZFX is the ability to put on 3 fully cured coats of protection on the same day. The "old" process (again for me as I don't detail for a living) was to wash, clay (using clean soap mixture), light wash, dry, polish, then apply sealant. Wait a minimum of 24 hrs- wash again (since the car would be driven), dry, then apply another coat of sealant. Wait a minimum of 24 hrs- wash again (since the car would be driven), dry, then apply another coat of sealant for a minimum of three days (or three weekends). Having two small children and a wife who really couldn't understand why detailing our daily drivers could take three days each (she expected it to be finished same day and fast :doh ) was just not something I could continue - especially with any level of enjoyment. :argue
For $20, ZFX added to Zaino has changed the process completely. I can wash, clay, wash, polish, and put on 3 coats of a very durable sealant (Z2 currently) in a matter of hours, not days. Since I have a black car and a white car I can't wait to try Z5 PRO on the black G35. For me the choice of mixing ZFX and Z2 in a bottle for 30 seconds to get 3 cured coats in one day versus my old process for 3 cured coats (with washing and drying included) of 3 days or 3 weekends is worth more than $20 and 30 seconds of mixing since my "free" time is limited and nearly non-existent. I have used several products (many not worth mentioning) to compare Zaino to including Souveran, P21S, and NXT (initial liquid version) and for me, and my time constraints, chasing the perfect (or near perfect) shine every 5-6 months beats chasing it every couple of weeks. Just works out so much better for me.