What do you mean about missing Amazon reviews? They have four pages of books on sale at Amazon.
I, personally, don't sim sub. That is because I am generally subbing the the exact publisher I want. So getting an offer from a 'also ran' publisher would just complicate things.
Naked Reader strikes me as a fairly generic, not terribly well known, publisher of all genres. Well established, well known, genre-specific publishers are generally preferable IMHO.
Also their Kindle ranks are very high. So if they are selling well, it isn't through Amazon.