This group, whoever they are, is providing hard-copy books that are otherwise unavailable. They are not, apparently, making editorial changes in the books but are simply providing exact copies of old, out-of-print, books that they have obtained. They use amazon.com as their store-front.
If you are searching for an old out-of-print book and find it available on amazon.com from this publisher, I would not hesitate to purchase it through this source. Furthermore, if anyone has purchased anything from this publisher, it would be good to see a review on the quality of the book binding. It appears that the books are published on demand in a paperback format. These are sometimes good quality and sometime poor.
I wouldn't necessarily browse their catalogue, but if one were looking for an old book and found it here, I'm not sure why one would not purchase it.