Japanese cars have the imagination of Japanese groupsets....a reflection of their homogenous society.
Yes, they are reliable...in fact both are...but you may die of boredom first...lol.

And yes, German quality is a myth of sorts and I know better than the rest because I have worked at both BMW and Mercedes in engineering and you haven't.
The reliability issue with German brands runs much deeper as it turns out. Both BMW and Mercedes are guilty of poor reliability in part because of their ridiculous complexity born out of carving out a marketing niche. To draw a bicycle analogy, some of the design features they offer are like BB30 and PF30...they may offer a benefit but at what is called a reliability cost. Complexity generally comes with an upside and downside...no free lunch for exclusivity. Where the crazy, inventive German's, unlike the more conservative and pedantic Japanese to a fault with less creativity get lost, its taking on too much risk to be different to set themselves apart. This arrogance to be the best has a price.
But they also don't manage their QC well on even more modest offerings like VW so no question Japanese cars with their more stilted designs...which have gotten better in recent years...largely by reverse engineering German products who set the standard for efficient performance cars in the 70's when Japanese and will add American cars were junk.

And of course, a parallel to the subject at hand is obtuse but it was to make a point about branding.
The Chinese frameset faithful will have to take their chances. Perhaps a better analogy is Hyundai. Chinese framesets without pedigree are like Hyundai in the early days..lol. A lottery. Hyundai didn't have a clue about due diligence and their vehicles reflected that. If there is a car company however to be respected, it is them. Their rise to prominence is simply remarkable. They make a very respectable product today when 10 years ago their cars were junk when getting started and their assent to the world stage has been meteoric with warranty second to none. Chinese products may some day have this cache but even their name brands today don't.

The posting of the BMW and Chinese joint venture went right over the head of all those that reviewed it and thought it bolstered the point of adding credence to Chinese manufacturing. The opposite is true which is precisely the point. With US or German or even Japanese oversight, China can product products second to none. There is nothing wrong with the work ethic of the Chinese people as they emerge from the stone age of a repressive society. They lack best practices in technology which btw changes each day but they are 10 years behind the US no matter how fast they steal our intellectual property. No doubt they will catch up...or perhaps this is possible because they kick out 5:1 engineers per capita compared to the US.
But to ride a no name carbon bike from China is a gamble. Btw, riding a Specialized or Trek carbon bike is a gamble as well...just a bigger gamble to ride a Chinese no name carbon bike.

In summary....You pays your money and you takes your chances.