I'll buy into this one, given I have a selection of 4 vehicles with varying degrees of paint quality and the fact I have both an Orbital and Rotary.
Firstly let me state that the PC (Porter Cable) Orbital is not sold in Australia and is not available in 240 Volt so a step down transformer is required.
On a newish vehicle I would only recommend using an Orbital as the rotary takes a bit of time to master and is aggressive on paint. You will take paint off an edge (eg. panel ridge) in not much more than a blink of an eye if you are not careful. A rotary on the other hand needs you to try really hard to damage the paint due to it not generating much heat which burns the paint and if you apply too much pressure the pad just vibrates and stops turning.
Some detailing nuts reckon the use of a rotary is only to impress the neighbours, maybe so, as it doesn't take too much effort by hand using a good commercially available product to take out a little swirling (or holograms as the experts call them).
I use sheepskin pads on the rotary (aggressive) and a selection of 5 different foam pads on the orbital, depending on what you are applying (cutting through to buffing).