MI 2 AZ,
I can't offer any more than you have said. Like most things in life, the answer is it depends. I tend to use more nylon pads because they're more convenient. I have all (sandpaper, nylon pads & Trizact) except Abralon pads, which may very well be the next Best Thing.
The grit does change, but more slowly than sandpaper. Used nylon pads last longer than used sandpaper and can be used to apply a finer matte surface, but with less control over the actual final grit than some other methods. Use what seems right to you.