I agree with stenoslave - don't use it. I believe that there is a specific chemical relationship between the Z5/Z2 and the Z6 that makes the Z6 as effective as it is.

 

The advantage of ZFX is that it allows you to apply the second coat of Z2 soon after the first coat is completed. One thing to point out is that if you wait overnight before applying the next coat, the paint should be washed to make sure that the surface is clean before another coat is applied (I don't have a garage .) To me that's more work. So to me ZFX is worth the money.

Last weekend was the first time the car was zainoed (after a clay bar prep.) One pleasant surprise was that I was able to put 2 coats of Z5 with only 1+oz!! followed by 1 coat of Z2 and the result was excellent. One bottle of Z2 should go a long way. I agree with the other board members about the other quantity suggestion.