3777 is consider an excellent rep, you can ask member higginsd to get a confirmation.
Movement 7750s with seconds at 9 are not that bad (they can actually be very good, same as 2892 or 2824). 7750s with seconds at 6 are ticking bombs, well known not to be reliable.
So it is. The "normal" 3777 is spot on the gen. I converted mine to a full franken (all gen but case and caseback) - but I never saw big differences between rep and gen parts. There are of course differences. The biggest "flaws" are the thickness of the main dial markers/lume, the circles of the subdials, the "white" of the hands, the lasting of the lume, the color of the hands stems and - the most concerning for me - all watches have the same serial number. I bet some money you wont spot any of this flaws from a distance of more than 1 meter. I would call it a super rep.
OK, the A7750 is miles away from an IWC 79320 in precision and finish. But it is a reliable movement, stable and precise enough for normal usage.
The 3777 PetitePrince isn't so good, I'm sorry to say this. A good rep, but no super rep. The dial color and the weak sunburst effect is the bigest flaw, followed by the circles of the subdials and the hands. It's relative easy to spot a rep.