And with the greatest respect, may be we were not just 'lucky' and the cheap Chinese chuck really is a good quality product. But if anyone is sceptical about these Chinese products, and they are fortunate enough to have the spare funds to invest in a so-called 'quality' British product such as the Pratt-Burnerd at about ten times the price, then that is their prerogative, although I have been informed even some 600-Group products now originate in Asia, maybe even their chucks for all I know.
For the purposes of amateur use in a back-shed workshop, my guess is that there wouldn't be anything much to choose between the two products except the price. If I recall correctly, about forty years ago now when Polish and Czech products were first beginning to enter the British market, there were reviews of the chucks in the model engineering press. The conclusion at that time was that the Polish chuck was superior and you would hardly want to own a Czech product. Well despite the review, I bought a Czech 4-jaw self-centring chuck for the Myford at an exhibition for no other reason than it was about twenty quid cheaper than the Polish version and looked exactly the same. I can tell you that in all those forty years it has hardly left the lathe and is as good as the day I bought it. Now I understand, Czech products are regarded as being some of the best in the world, so maybe one day all the prejudice against Chinese products, which I think is more founded in xenophobia and rather than established fact, will disappear too. (BTW, I do understand the political implications of China's manufacturing prowess, but that debate is not for this forum).