This movie is 'not' a remake of Devdas. Probably, Anurag Kashyap wanted to borrow the base story from there, but I repeat if you are a big fan of Devdas then this movie isn't for you. But then again this is one of the most insane movies to come out of Bollywood. You might probably end up with a headache after watching it, but its completely worth it. There are few movies with such exceptional cinematography and music which blends completely with the movie.
The characters are well defined, but also over the top. Abhay puts in a real perfect act of a self-sympathetic fool, who drinks and does drugs just in the obsession of Paro. He becomes completely lost and finally ends up in the arms of Chanda. Paro has apparently never known the words 'shy' nor 'blush'. Chanda has seen a lot of pain and is the only character who slowly becomes sure of herself.
This movie is more about how they have painted the characters rather than the characters themselves. This is a first in Bollywood and I have never heard such dark, yet at times beautiful music. Its loud at times, but Amit Trivedi's work is a sheer genius one. If you do end up liking the movie, you would give half the credit to the music.
Anurag and the entire team have poured in their heart for this movie. Most of the work and the ideas are genuine and is not picked up from some other random movie. It is an 'its own movie'.