What color is your XF, does the finish look dull or visually looks like it does not have wax on it? I have used the products that you have mentioned above with great results. I wax my Roadster Limited at least 3 times a month, and the finish between washes and waxing is always as smooth as glass. Have you tried removing all of the wax and check the condition of your paint, the use of a clay bar may be in order. Here is the regiment that I follow:

1) Wash car twice, I use meguiars NXT Car Wash...then dry the car.

2) Apply 2 "THIN" coats of 3M Imperial Hand Glaze, allow the glaze to cure for about 15 minutes between coats.

3) Apply 2 "THIN" coats of Meguiars NXT wax, allow the wax to cure for about 15 minutes between coats.

4) Apply 2 "THIN" coats of Turtlewax ICE synthetic carnauba wax, this will make the paint pop and give you depth of color. a few hours later follow up with the Turtle Wax ICE detailer and you are good to go.

ALSO ALWAYS USE GOOD MICRO FIBER CLOTHS.

My car always looks like it is made of black glass, so I have been told. I know this is alot of work, but well worth it.