Nates- Welcome to Autopia. I'm pretty sure you'll like the 1Z polishes.
It's been a while since I've used FI-II, but I'll give you my $0.02.
The UP is more aggressive than the FI-II and doesn't leave quite as fine a finish, at least for me. Following up with the PP *does* make for a very nice finish; it removes the micromarring left by the UP.
The PP is more aggressive than the 3M SMR, and must be worked thoroughly to fully break down. Although PP leaves wax behind, it is different from the fillers in the SMR in that there seems to be less of the temporary concealment that SMR provides. Good, in that you have a better idea of what condition your paint is really in; bad in that, well, less marring is hidden if it's still there.
The waxes in PP provide far more protection than the 3M products. If you don't immediately apply your LSP, you'll be OK until the next wash and you can just do it then.
As Greg said, the 1Z polishes stay wet a long time. Try to work them until they pretty much go away. It's not like you'll work them too long.
I use a cutting pad with the UP, then switch to a cutting pad with PP. Then a polishing pad with PP. You might try experimenting with just UP/polishing, but the above 3-step process works best for me. I work the polishes a little while at a sorta slow (for me) speed like 4 so the abrasives don't break down too fast, then I speed it up to 6. Most of the work ends up getting done at 6, the slow speed is just when I start out. I've used these with the Cyclo (fixed speed, sorta fast) with great results, so they appear to be pretty tolerant of different application methods.