Mark XVI/Mark XVII/LPP are basically the same as Gen (all from MK). The dial markings are a little different (thinner) on XVI, and the crown is thicker on all of them. Crown is the only instant tell, and obviously only for rep experts. Otherwise, perfect reps, same sized case as gen, even AR is pretty close to IWC standarts (pretty reflective). IWC XVII LPP has the most accurate dial of them all, in my opinion, but again, crown is a tell.
So they might not be perfect out of the box, but first class for sure. I'm completely sure on XVI and XVII LPP, not so sure about XVII.
@pippo, could you help me with defending those?
According to Portofino, there are no flaws in it, to my untrained eye. White version is just the best out of the box dress watch rep. Maybe I'm wrong, but it should definitely be a NWBIG.