I use the real Febreze, I feel I "owe it" to the customers to give them something good if I'm going to charge a premium for it. Febreze still costs less than Fragramatics' oil-based fragrance ($12/gallon vs. $20 plus shipping for oil-based fragrance).
Febreze does contain up to 5% ethanol, so its freeze point is lower than that of water, just not by much. I'm more concerned about its flash point, which is 140?F - it gets hotter than that in my car on a summer day.
Sam's has started carrying the extra-strength Febreze again. For $9 you get a 32-oz and a 16-oz bottle.
Our Doyle combos are already labeled not to spray the fragrances on vinyl, plastic or leather, so that's covered. I just call it "Deodorizer" on the selector.