There's not a lot of information on the site, probably because the site is still under construction. One thing that is a yellow flag is they breed Yorkies too. The reason why that's a yellow flag is because most ethical and reputable breeders only focus on one breed.
see I have my own opinions on this. While breeders can/do breed others breeds I personally get a bit leery of breeders that do majorly different breeds. Like I'm fine with someone who breeds GSDs Malinois and/or dutch sheps but a GSd and yorkie are very different breeds so while they may be perfectly good breeders I personally would at least do a lot of research on their knowledge of GSDs and also figure out why they breeds such different dogs.