I got a free review copy from OP ...I got 4 articles but maybe my badluck or something, articles I got was of really bad quality.None of the articles made any sense to the articles title.Maybe the reason behind this was the topic (narrow niche) I had given to OP.
So I what think is articles are not of same quality...Some are good,Some are really bad.If you have broad niche then one can expect that OP must be having large number of articles & can replace if you get some bad quality articles but if you are looking into a narrow niche articles then OP must be having less number of articles & ratio of good articles will also be less i believe....