Lots of things are made in China. Probably most of the items you purchase from most retailers. As a retailer and parts designer in this industry I do all I can do make sure that no matter where my parts are produced they are of the highest quality. That can easily be done in China or Taiwan with the correct contacts and practices. Most of the parts I design are made in the US due to production quantities and pricing, but some of my items that are made in larger runs are made in China and I have yet to have a significant quality issue with those parts.
Just my $.02.
Beyond that, one should not use drilled rotors on a street car. Especially ones that are drilled from a blank. There are some that have the holes cast in and those are fine to use as they tend to not develop cracking issues. Drilled rotors created from blanks will almost always have cracks propagating from the holes. For the same look and function but with much longer service life go dimpled.