I did a grey one a year ago, its huge. Paint was easily corrected with Rupes LHR15ES and Menzerna PF2500, had to go back to my pic library to see what I used.
I did a black 1 few months ago. Paint is very cooperative to work on. I'd say it was med-hard.. I used Megs Ultimate Compound followed by M205 on my G21 with LC HD Orbital Foam Pads. [Blue/Orange]
Make sure you have your firm exterior detail brushes on hand because it's more than likely to have built up contaminants in between the letters on the rear Panamera emblem. You'll need a proper tool to clean it up.