On October 3, 2006 the FACT reading group discussed "A Scanner Darkly" by Philip K. Dick. Of 6 people who attended the discussion, only 2 people finished reading, or rather re-reading it. Some others had read it long ago when it first came out. One reader commented that he enjoyed "A Scanner Darkly" back then, but it didn't seem as good the second time around. This change in perspective was attributed to the reader's head being in a different place than it was a couple of decades ago. :-)
Two readers said they liked this book because they like books about paranoia. One reader could really relate to the paranoia, experienced by the protagonist; in her view, paranoia was inseparable from the 1965-75 drug era that she thought Philip Dick portrayed so well. (Actually, "A Scanner Darkly" is set in 1994, but I guess its "real age" is the 1960s, in the same way that the real era in which Ray Bradbury's novels are set is the 1930s, regardless of what time period the author claims they are set in.) Paranoia pervaded her childhood in the 50s (House Un-American Activities Committee); she was also forced to go to a very strict fundamentalist church and could not speak to anyone forthrightly about her concerns. Every idea in her head had to be kept hidden from adults. So she said she could relate quite well to the paranoia the protagonist is experiencing.
One thing she found missing in the book's portrayal of the drug subculture of the 60s was the musical motif. This time period was intensely focused on music, but there's no mention of music in the book. However, Philip K. Dick captured a lot of the realities of the drug era really well. As an example, she said, "there were people who were a little on the speed-freaky edge, who would really start motormouthing, and you have big chunky paragraphs full of blathering on and on, which was really typical of some people."
Another member of the group disliked this book for pretty much the same reasons that caused the previously mentioned reader to relate well to it. He said, "I found this book difficult to read. It was dealing with a culture that's completely not optimistic, and so nothing good was going to happen in the book. It was very depressing. The book has occasional humor in it, for example, the story about the older brother who was a bug. Philip Dick does a good job of getting into people's heads, but I did not want to get into these people's heads. I could not sympathize with them. I didn't want to think like them. " That's despite the fact that he liked some of Philip K. Dick's earlier books like "Do Androids Dream of Electric Sheep?" As far as portrayal of a split personality, there have been better books on that, too, in his opinion.
The group universally agreed that "A Scanner Darkly" is not a science fiction book, and that it was chosen for reading only because it was written by an author who is known for writing science fiction. :-)
My opinion of the book can be found in this post in my "official" science fiction blog, but beware -- it's laden with spoilers.