I used a microfiber bonnet over a foam pad on a rotary when I was experimenting on an older car on my polishing technique, in preparation for the Porsche. It worked ok. I did need to periodically clean the microfiber bonnet, but I found I was able to get good correction by pressing down kind of hard. Maybe the microfiber has abrasive qualities that can polish paint all by itself? Sure seemed like that. (A "bonnet" by the way, means a shower-cap like thing with elastic edges, which covers over something.)
When initially trying foam pads, I found the firmer foam pads - I used a yellow, for example, would sort of disintegrate when used hard. That was when I was using Menzerna polish/compound, SF1500 it was called I think, which really heats up. Maybe I didn't use an aggressive enough compound for the amount of correction I was trying to do, so was trying to make up for it by pressing down harder. The pad was supposedly high-end, expensive. Didn't last, probably from my heavy use.
More recently, after going to a dual-action machine with softer foam pads (I got a load of overseas foam pads on eBay for cheap!), I'm getting good results, and more ease of doing it than ever, using a meguiars M100 compound. I really like that compound because:
A. It's aggressive - doesn't take forever. Can even do very impressive things with it just with a hand pad, in places where the machine doesn't fit!
B. It's not "diminishing", so there is more flexibility on how long it can be worked, and no minimum work time. So nice not having to always take forever with the stuff! (It still gets "spent" after a while of course, but I understand it's more a function of it picking up residue, which means cleaning or swapping the pads.) And can't forget:
C. It runs so cool! (Imparts very little heat into the paint, totally different than Menzerna).
I still haven't fully polished the Porsche, but I am very happy with the technique I've arrived at. Here are some pictures of a polished hardtop I did, which came out *outstanding*!
http://986forum.com/forums/539976-post12.html
If there is enough interest in talking car detailing, it might make sense to ask the 986 forum admins to add a subforum on car detailing! What do you guys think? What with how many Porsche folks love to fuss over their cars, it seems like a natural fit here.
I got really turned off by autogeek forums after finding out they delete discussions about products they don't sell, and after having some of my contributions on things like eBay pads and harbor freight dial action polisher tips being deleted there. I won't be wasting any more of my time there. Suggest others take note of the autogeek forum censorship policies, and steer clear if you're looking for an unbiased information source.
Cheers