I think it depends.  If the reviews are only for one Spa and all reviews of girls for the one Spa are all glowing, it’s definitely suspicious IMO.  Also, I think if the one Spa rotate the girls so often why bother writing reviews because by the time the reviews post the girls may have left.  

Maybe if it’s a nonFS spa and the girls are there for months or longer; then maybe the person is just sharing his experiences?    

As a monger, I personally think reviews are helpful when I’m trying to decide what AMPs to go try.  Again if I see a reviewer only post reviews for ONE spa then I won’t be going there.  Just my 2 cents when I see reviews for AMPs.