Hi Frank,
For that kind of lamp, the average Chinese made versions put out roughly 30% lower beam intensity and the lifetime is rarely more than half that of the equivalent European made product. Colour temperature also drops by 200K or so. Additionally you should expect between 2 and 5% of a batch of Chinese PAR lamps to fail within the first hundred hours or so of life. Nevertheless, their sale price is half that of the European versions, and for the majority of customers that is the deciding factor when choosing a replacement lamp. Chinese made lamps from the big brand names are always somewhat better (they achieve the rated life), but all are less efficient, and still suffer a high percentage of failures in the first 100 hours.
James.