The Hexar AF, not RF ?
If you're looking at the AF, then it is a perfect compliment to the F4.
My good pal, and fellow Apug-er, has some info on both at his site:
The Hexar might be the very camera to grab when you have 5 minutes to pack for that surprise round-the-world trip. It is just superb.
The F4 is a very, very good AF camera and a wonderful Manual focus camera.
Great stuff: good luck.