I'm not sure I can say I like this. The subject matter is quite unpalatable, really. I do have this attraction to occult detective stories, and that's Hellblazer in a nutshell. Constantine is not what I'd call a good man. His compass is flawed, but in his own way, he does try to make things right or do the right thing, even if it's for selfish reasons. He considers himself neutral in the good versus evil war. However, his acts more often than not add to the good side of things. If not, I probably would write him off. The tragic thing about Constantine is that he has left a trail of destruction in his wake, people whose lives were destroyed or taken due in part to a connection to him. I think that this weighs on Constantine, but it doesn't seem to motivate him to change his crooked ways. I did like how he manages to manipulate demons who think they have the upper hand. I wouldn't ever recommend making deals with demons, mind you, but it's amusing that Constantine does and always pulls a fast one over them.
The artwork is vivid, but it doesn't really appeal to me (a lot of yucky imagery), although I like Constantine's looks. Sometimes he looks like Billy Idol, sometimes more like a young Sting. I can see how inspired Joss Whedon was in his crafting of Spike and Giles' characters. Spike has Constantine's punk, don't care leanings, and his use of British insults. Giles' youthful peccadilloes seem very much like Constantine's youthful dabblings in the occult.
I'll keep reading this series, but I think this is one I will have to take regular breaks in between. However, I'm enjoying getting Constantine's background, especially since I am loving Justice League Dark, and since NBC is having a Constatine series starting up this fall.