I think I identified with this book so much because there has been a lot of addiction in my family including hard core drugs. So, I recognized the actions of the characters from similar insane incidents from my own family's history. There is a scene in the book where the characters are sitting around in the living room in Arctor's house and have just gotten high. Barris has bought a bike from the neighbor but and he thinks the neighbor screwed him because he told him the wrong number of gears. They all sit there trying to figure out how many gears the thing has and they keep adding them instead of multiplying the front by the rear. It's this entire argument and they end up going out to confront the guy who sold him the bike for ripping them off and the guy has to explain to them how they are figuring it out wrong. That is a total high on type of conversation and it's one of the funniest things I've ever read in a book. There are so many other incidents in the book where I just found myself shaking my head thinking, "Yup, recognize that, I remember when my brother, my uncle, my..." and so on.
But that aside, I have read 3 Dick books and am in the middle of a 4th and I still think I like Scanner the most right now. The entire book just flows from characters to pacing, and as I will explain more in my next review, I think Dick is more than just a sci-fi writer - I think he actually asks important questions in his books about humanity.