Guardian article about the Page 99 test, which posits that an author is trying hard to impress on page 1, so you’re better off checking page 99, far enough in to test the author in full swing and the plot but not so far as to reveal plot twists, to assess the whole. Further:
A new website, page99test.com, launches next month to test that premise. It will offer (courageous) authors and aspiring authors the chance to upload the 99th pages of their works and invite readers to comment on whether they would buy, or like to read, the rest.

Thought you might be interested in the ORIGINAL Page 99 Test…and the Page 69 Test.
http://page99test.blogspot.com/
http://page69test.blogspot.com/
Thanks for those links