My guess is that it's a scam & that's why the English is so messed up. Even if it were true that Brother branded machines were identical to some generic name, Brother is not going to tell you that. It would be counterproductive. Beyond that, there are usually legalities that mean that even though 2 products are made by the same company, the company does not provide the same level of support for both. In addition, they usually create a separate legal entity for the non-branded product so that if a consumer sues, the well-known Brand (company) is not liable. Instead, the no-name company with limited assets is and it may not even be legal to bring it up in court that the 2 companies are related.

For those reasons, and more, if it is a major purchase, I usually will buy from a reputable dealer by a reputable manufacturer. I know that a large, established company like Viking, Brother or Singer is going to stand by their product and if something is really defective, they will repair or replace it without issue. Sewing machines are so expensive, I would hate to find out that I couldn't get parts, service or replacements on my machine after spending so much money (even if it did save me $100 at point-of-purchase). But that's just my take on it.