I'm not sure about what they sold a few years ago, but what they sell now...well you can test them yourself.
Quality issue aside, I find what they did was very untehical, they just based all of their products on our designs. Obviously they can make them cheaper as they don't have any R&D cost, and they don't do TUV testing (as you can see in their website, they talk about european homologation, not germany E1, much more strict on noise levels). The cats are a lot cheaper than the HJS we use.