Don't get me wrong, I love using the rotary.
For a dark green car swirled to hell? Neither of them are sufficient. For a badly swirled car, you'll definitely have to start with something stronger, like DACP or FI-II, peferably with a rotary. It's difficult, grueling work to remove deep swirls by hand. Even with the PC, restoring a badly swirled car is a tough undertaking. However, with the rotary, the process will go MUCH faster and with incomparably better results.
For light imperfections that inevitably build, even on a carefully detailed car (I should mention that I have a flat black car), I prefer removing them by hand using a light swirl-remover like 3M's SMR, just a few times a year.
When working by hand, I prefer 3M's swirl remover, but that's just my personal preference. #9 works well also. With both product, I get no haze, no marring, just a perfectly swirl-free surface. It's fine to have individual preferences, but for the most part, all good quality polishes will do the job.
Not sure how long it takes for me to work the product into the paint. The terry cloth seems to 'consume' the product pretty quickly, so if I were to make a guess, I would say it only takes about 45-60 seconds till the surface is nearly clear and dry and ready to be buffed. This is also another reason why I like polishing by hand. For spot-polishing, it's 'quicker' than when using the PC, which requires you to work the product into a single area for 2 minutes minimum...and I get just as good results by hand as I do by PC.