I'm the other way around. I loved the atmosphere and the slow pace when I first saw it. But ever since I read the book I can't enjoy it the same way. I feel it just doesn't do it justice.
The movie is literary much darker and takes place in a claustrophobic decaying chaos of a enormous city. I has the slow pace of a 1940th film noir and while the theme of what real really entails is central, it just one part in the whole vision.
And everytime I try to watch it I get bored quick.
I think I would have much more apreciate it, the atmosphere et all, if I hadn't read the book before. And I realy regret it because I know it's a good movie.
I still enjoyed both films but that aspect of them (both) really sucked.