I have a DVD that came with the PC that mentions only going to 5, but doesn't tell you why. Now that I know about backing plate failure and Velcro failure, I know what to watch for. I may not have gone to 6 on my own, but heard others recommending that, along with the 4" pads for paint correction. It definitely does work well while it works.
Since we're dealing with a number of variables here, I'm not sure that changing products, pads, arm speed and pressure will fully duplicate the results you would get from the "6" speed, but I'm not sure that they wouldn't either, and since I don't want to ruin my paint from a damaged backing plate or failed Velcro, I'll keep the speed down. Like others, I don't have a rotary (but will probably get one eventually), and was trying to correct 3 years of poor auto care ( didn't really know any better, and didn't have the time to detail) and 3 years of a dealer washing my car and causing all sorts of problems. Then, the dealer repainted the hood and fenders because I pointed out how badly they had scratched the car, and it was chipping like crazy (it's an '03 Mercedes with single stage black paint- they topped with clearcoat). The rotary guy at the dealer was terrible, causing massive holograms, buffer marks and scratches. They also said they would buff out the scratches all over the car and all they did was throw on wax with fillers and caused more damage in the process.
I've been working on the car off and on for weeks and it really is looking great. Had I known the time it would take with the PC, I may have gotten a rotary, but I am somewhat leery of tring one. I've seen 4 people use them in this area, 2 of these are supposedly "experts", or "masters", and I haven't seen one that can leave the car in acceptable shape. So, I'm forced to learn it and do it myself. I also have an '06 Ford F-250 Harley Davidson Crew Cab in black, and I want to maintain it in it's present, almost perfect condition. Thanks for all the input and suggestions. BTW, I already got the replacement backing plate from AutoGeek. They shipped it Next Day Air at their cost. Great place.
These are the "before pics" and I'll post more pics of the Benz when I get it done.