This is the only Dean Koontz book I've read, and it was recommended to me as his best. I did enjoy it, but I don't think I'd actively seek out any others. I liked it, but at the same time somehow didn't like it... yet did like it. As an example of what I mean, I thought the book was way too long, felt annoyed by the book and yet I couldn't stop reading it. I stayed up until 3AM this morning reading, and was still trying to convince myself to read one more chapter when I turned off the light. 
 A lot of the things I'd like to be left to think about on my own were discussed explicitly by the characters, like the perils/merits of genetic experimentation. 
 I thought The Outsider was a fantastic, creepy character, and I wish Dean Koontz had written a book that was just about The Outsider or a similar character.