I know that the "one polish, numerous pads" thing is all the rage right now, but I guess I'm a bit old fashioned; I vary the polish, and for the most part, stay with one pad, and that's a zero bite soft one. Unless I'm doing *serious* compounding, then I'll go with a cutting pad (normally a SurBuf on a PC, or PFW or some other type of wool on a rotary).
Let's say you take some plain old baby oil, and use it to lubricate various foam pads, some with bite, and one with no bite. Now apply some baby oil to a pad, and start polishing your car with it. What is the finish that the pad leaves gonna look like? Since the baby oil has no abrasives, the finish is going to look only as good as the pad used. If you did this with a cutting pad, it's not gonna look very good. If you did it with a zero bite pad, it'll look pretty good. So what's the point of this little experiment? The point is that polishes are only going to finish down as well *as the pad you used to apply it*. If you use anything other than a zero bite pad, the chances are pretty good that the finish you're left with was what the *pad* was capable of finishing down to, *not* what the *polish* was capable of finishing down to.
So when I use M105, I start out using it with a zero bite pad. And that way I know that it is finishing down as well as the *polish* is capable of finishing, not the pad. As long as this is giving me enough correction, I'll stick with that zero bite pad through out the compounding polishing step. If it's not, I'll either do another application of M105, or step up to a pad with a bit of bite.
But for final polishing, IMO, the very best pad you can use is a zero bite pad. That way, once again, you'll be finishing down to the level that the *polish* is capable of finishing to, and not the pad. I've often wondered why people do the final polishing step with a pad that has cut to it; you're just not getting the best gloss you can get when the pad is hindering the polishes finishing abilities.
IMO, there are very few times when anything other than a zero bite pad is needed for KBM/M105. You'll still get serious correction (without removing additional clear coat unnecessarily), with a finish as good as the polish is capable of giving (and in the case of a DA/105, that's gonna be pretty darn good). Again, IMO, it's better to use two applications of M105 with a zero bite pad, than step up to a cutting pad and just going over it once (this is for non-pros, for obvious reasons).
So, unless I need *serious* correction done in one step, I really like staying with a zero bite pad, then changing the polish as appropriate for the current polishing step.