I don't think anyone who would buy this thing was ever really a potential buyer of a Bubble King. I wouldn't consider buying one personally for two major reasons:
1 - There is always a quality trade-off with something like this. After reading stories of things that went wrong with crappy knock-offs, I just wouldn't feel safe putting it in contact with my aquarium. After all the money I've spent on my reef, hell no! Even if many people have used it with no problems, I still wouldn't trust it. There is really no QC with these kinds of products. One batch of them could be completely different from the other. How would I know that I didn't get one from a bad batch before it nuked my tank? The manufacturers don't care, and who is going to make them care?
2 - I really prefer to see the person/people who have spent the time and effort to design and engineer something reap the benefits. IMO, if the BK has a patent that this product infringes, then selling these is no better than theft and buying them is no better than buying stolen goods. With a blatant copy like this, even if there is no patent, I still don't like it. I don't mind as much buying from a legitimate company that uses Chinese manufacturing. However, copy shops in China are an entirely different animal.