In the Auto Detailing world, there are generally two types of polishers - rotary and random orbital (RO). The Rotex 150 is unique. It can act as an RO polisher and as a "hybrid" between rotary and RO in Rotex mode.
Rotary polishers are best used by professionals only. A double-edged benefit of rotary polishers is that they can generate heat. This is great for removing deeper scratches and more serious defects from auto paint. BUT... They have to be used carefully because they can burn through the paint quickly. I won't use one.
RO-only polishers are used by amateur detailers. The standard is the Porter Cable 7424 (hearafter referred to as "PC"). I have a similar one that's the same except for a larger counter weight suited for for larger polishing pads (sponges).
While it's possible to burn paint with an RO polisher, it's VERY difficult unless you are really trying. With a good quality, more agressive polish, a more intense pad (sponge), and some work, they can remove most fairly serious paint defects. The downside is that you have to change to the more aggressive pads and polish, spend more time at it, and they won't remove defects that a rotary will nail pretty easily. But again, they are safe!
And that brings us to the RO150 Rotex. The RO mode can be used just like the PC - safe, easy, and useful. When you encounter a more serious defect, switching to Rotex mode can resolve many defects quickly without changing pads or polishes. Or, you can change out the backing plate (pad in Fest.ool terms) and pad (sponge) quickly and easily for the bad defect, and then switch back to finish the job. Changing the speeds up and down, with or without changing pads modes and/or backing plates/pads gives you a broad range of options.
That brings us the issue of burning paint. Yes, you could burn the paint more easily in Rotex mode. But you'd have to try pretty hard. Use Rotex mode, high speed, a yellow (agressive) pad, and a heavy cut rubbing compound on a door edge and you go through the paint pretty quickly. Then again, you can do that with a PC polisher too. It would just take a little longer. OTOH...
Use Rotex mode, speed set at 3.5 to 4.5, a normal polishing pad, a standard polish (like Menzerna Intensive Polish or Final Polish II, or Zaino PC) on a flat panel and your chance of burning paint is minimal. The key technique is to always use the least aggressive mode, speed, pad, and polish combo to get the job done in a reasonable time. And always be careful of edges (like door edges).
Turning to polishes, I'm not a fan of McGuires products. I think that they are better now, but in the past most auto detailing enthusiasts would not touch them. I've used Menzerna, 3M, and (more recently) Zaino PC polishes successfully. If there is a knock against Menzerna polishes, it's that they take longer to break down (work). Rotex mode helps with this.
Regarding lambswool bonnets, I have only one piece of advice - NEVER use them on car paint. They are incredibly aggressive. Stick with foam - either Festool or other brand (I use Lake Country pads).
Regards,
Dan.
p.s. the only time I would use a lambs wool bonnet on car paint would be to rub out a freshly painted car. Of course, if you've just painted your car, then you know far more about this than I do. You certainly don't need my advice. ;D