The good thing in their direction is that they don't need to be good right away. China government will force Chinese airline companies to buy hundred of them, good or not.
But with all the western technologies in it, systems, avionics, and engines, it should not be bad, anyway.
It could be heavier than competition and not too user-friendly to maintain, but once again, with the Chinese subsidies, it should be affordable to compensate.
And they will gain experience for future products.