The first anti-JW book I ever read (when I was in my late teens) was Thirty Years a Watchtower Slave. It made me laugh. I turned page after page and smirked and sneered, considering what a pathetic selfish fool of a man this Schnell was. I threw it away.
The second anti-JW book I read (when I was in my early 40s) was Crisis of Conscience. It made me cry, and made me sick. I threw it away.
Now, since I have reread both of them, I see the same story, told from different viewpoints, and with a different set of historical perspectives. TYWS has many very little direct documentation, but can now (thanks to resources made available to the general public just within the last few years) be documented nonetheless. COC has much documentation.
I think both can be considered worthy works.
As a small example of the comparison (from TYWS, p. 140):
Thus, during the years from 1935 to 1938, in the twilight of the Theocracy, we worked in New York City and other metropolitan centers to develop this system of things. We had as our goal to capture, brain wash and establish thousands of Kingdom Publishers, making them all think alike, like robots. When in 1938 the Theocracy was decreed, all these fell down and in abject submission before this newly erected "Image of the Beast" of the Watch Tower religion of "buying and selling." (Rev. 13)
All the companies of Jehovah's Witnesses at that time voted in a resolution declaring that henceforth and always they would accept all instructions and appointments handed down by the Watchtower Society. All shreads of congregational independence was thus given up, together with any semblance of a personal Christian religion. A new world organization based on the concept of robot-like obedience and performance had now been realized and would now expand to become a New World Society. It is described by Jehovah's Witnesses as God's Organization or Kingdom. It is in actuality nothing more than a dictatorship of the Faithful and Wise Servant Class in Brooklyn.
Ashamedly I confess here that I had a part in devising and originating such channels of indoctrination...
I do not have a copy of COC to hand, and am perhaps therefore at a disadvantage, but I submit that the above descriptions (time-forwarded, of course) reflect much the same experience, and much the same sentiment, as Ray Franz expressed.