Genuine and common sense tip. You want something that can be easily found on a dark stage floor/ back room. For something so expensive, they’re easily lost.
I can think of 3+2 examples but not many 3+1. Could they potentially be under license? The prototype Z series had 3+1 but IIRC Sire were threatened unless they modified it.
it looks incredible. If I was to go down the luthier build route again, I know rather than dictate the wood top I’d be enquiring with what they have first. Sometimes they have something extra special that can surprise you.