I use Maguire's #3 carnuba wax (liquid), too.
When the wax no longer wants to buff out easily (or the paint still looks like there's foreign matter that won't come off), then I will use the #1 (cleaner), #2 (polish), and #3 (wax), all in that order. It takes 3 times as long to do the car, but I don't have to do the 3-steps every time...really only once or twice a year or whenever I've neglected my regular washing and waxing routine.
I have a question: Does NuFinish work on top of the wax, or what? If NuFinish isn't a wax, then what is it, and can you still wax? :?