The 3M PIII-MG works very well for minor swirls on a finish. If a finish is loaded with swirls/defects, then I reach for the DACP, followed by 3M PIII-MG and Menzerna FP or Megs Machine glaze as a final ultra-fine polish/glaze prior to sealant. If I were to wax a finish, I then use 3M PIII-FG as it has carnuba in it to assist in really brining up a fine mirror finish prior to waxing it. Then I wax with Souveran or S100 or other high-end wax.
Once swirls are gone, then it's a matter of brining up the shine reflection, and that's done by using a very fine polish/glaze and I use a grey finish pad so ONLY the polish does the work and not the pad. More like applying it by hand only much faster and better results. I only work a small area to check the level of refectivity and if it's a marked improvement, I continue to the rest of the car.
Prepping a finish is where you get that mirror look, without the effort, wax just lays over it and gives a slight better look, but not what it could really be. This is more prevelent with Zaino or other sealants that need an absolutly clean, high-polished finish for them to have the effect they were designed for. Zaino will highlight ANY defects. Not sure on other sealants.
If Zaino or sealants are to be used, you MUST wash off all the oils from the polishes or glaze for it to bond. For Zaino, I wash with Dawn then Z7 after polishing/glazing prior to ZFX/new Z5. Spray with Z6 B4 and after each coat. You can see the results in my pic below and others I posted.
Regards,
Deanski