Let me also share some insights of what's going on in China. Patek and RM are getting really popular in China in the last 2-3 years, therefore demand are there in the gen and rep market.
Let's start off with patek, people in China are getting richer and richer, so the demand of buying luxury goods is increasing. In the past, people from china either buy Rolex or buy the most expensive watch in the store (different brand), they believe buying the most expensive watch can buy them taste (some would think that). However, in the last few years, the steel model on Rolex has increased dramatically, and more and more people in China are getting wealthier, therefore they target the next level, Patek. The reason being is why should I buy the marked up steel daytona when I can buy a PP 5711 that is league above rolex? As many of you may know that PP chooses who to sell, which makes it more exclusive, people love to get what they can't get, I'm sure that's human nature. Meanwhile, 2016 was nautilus 40th anniversary, the sky rocket price of 40th nautilus model has made more people aware of the nautilus, therefore that's when nautilus heat has started all over the world.
The demand for any rep nautilus model is extremely high and the sales were great in the past too, therefore you'll see a lot more nautilus models in the future from different factories, not just the factories you mentioned, which means more competition = better quality to distinguish themselves out from the market, kind of a mutual benefit.
The other type of chinese buyer are the one who love to buy the most expensive and exclusive watch, RM suits this category well and the brand is pretty well known in the current market (in china, the rap culture is arising as well as a lot of celebrities in the world are wearing RMs)
A lot of factories would like to do RM, since there are not many RM reps out there compare to the other watch brands, but the main problem is they are pretty hard for any new factory attempt to rep them correctly. Some attempted, which mostly would appeared to be low end quality. As many factories don't have the budget to buy the gen to rep, plus the profit margin is not great if they buy an actual gen to rep. Since the gen of the RM is pretty expensive, the cost will be significantly higher. Would you buy a 90% correct AP replica (replicate from gen) or a 50% accurate RM for 600USD? I know some of you do, but not a lot and those people do not justify the whole rep market.
I heard that some people have asked why not buy some cheaper RM gen to replicate? The problem is the demand is not great, most people who know RM only know about the RM011, RM052, RM35 and RM55 etc (iconic models), not so much about the other models (it's like AP for royal oak and PP for nautilus, not many people know about PP calatrava). Look at rm033, the sales were horrible, even though it was a good attempt.
Imagine the factory sell the low end reps for 1 - 200USD, the material and development costs only costing around 10-20%, while the rest is profit and the sales is going to be high as the demand are there mainly due to the large population of people would like to try out the RM, as well as the price is extremely attractive for them.
If a factory buys the gen for replication, the gen and development costs will take a huge fraction of the price, but the first version will likely to be only around 80% close to gen and it is charging 1000USD or above, do you think the sales will go well? Look at rm001, many people have suggested that they love to have a tourbillon movement on the RM, but who actually bought the rm001? I think there are less than 5 people who bought it in this forum, because it is expensive. I know some of you might say because it doesn't look identical to gen, but if they put more effort in and charge 2000USD for a 90% rep? Look at how JB double tourbillon turns out, people love it but too expensive for the majority of the market.
If ZF has placed a real tourbillon onto the rm52, it should definitely has the same result as the rm001, but rather they target the middle + high end community (cheaper but less accurate since it is hard to see the tourbilllon movement inside ), to satisfy most of the people for the market as well as to cover the costs of buying the gen rm011.
Most people in China don't really put much effort into finding out how close is their rep compare to gen (if there is no RWI, I'm sure many people not just from China would behave like this), most of the people solely listen to what TDs say about the watch or to look at the comparison photo/video of gen vs rep, and they will just buy it straight away, since not many people around them would likely to know the differences between rep and gen, and their buying behaviours are quite impulsive, so like on the next day they will buy another watch. It is also relatively similar for the people outside of china when they know nothing about replica, some people believe fake/replica should be cheap, and buying a replica for over 300USD is absurd, that's why the low end rep market is really popular.
Hope this help you guys to understand the whole situation better
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