I've used the Griot's version of PC7424, and love it. I also use the Griot's line of machine polishes with good success. They do not remove ALL swirls, which ultimately is what you want, right? To truly do this, it looks like a direct drive polishing machine is the way to go. There's a HUGE- repeat HUGE- risk with these machines and being too aggresive. You can eliminate layers of paint quickly if you aren't paying attention.

Having said that, the Griot's buffer and product line will give you a nice finish, better than "buffing and waxing" by hand. I do not like the Best of show wax from Griot's, as it tends to dull the polished paint I just worked so hard to get. I'm switching back to Meguiar's High Tech yellow wax, as I find it much easier to work with, and won't dry white or discolor plastic or vinyl trim.

Autopia has lots of Zaino followers; kind of like a cult over there. I'm not sold yet since the Meguiars product is half the price.

To see what a direct drive machine and the right product can do to a black Porsche, see this detail. You may have to register to see pictures, but it's worth the look.

Ultimate Black Porsche detail

 

I would be very careful of using a machine to polish if you haven't done it before and have nobody to show you.

I would also say don't buy on price. For instance, Zaino isn't the cheapest but it lasts a lot longer than most. It is very easy to "top up" and maintain the finish. Having a Guards Red car certainly makes you focus on results and length of time they last. I find Meguiars and Autoglym to last no time at all, Zymol to be a bit better but nothing comes close to Zaino.

Zaino probably doesn't produce the ultimate finish but it is still very impressive. And it really is the lazy man's system. Only the truly obsessed would not be happy with a Zaino finish and they are the ones that seem to be happy to spend 1 weekend in 4 preparing their cars. I personally would rather be driving!