The cinematography in this is amazing. The yellow shots of life behind wire, The Zone being in full color, the use of blues. There are long shots of "nothing" that allow you to enter the same mind set as the people you are watching. The 4th wall is broken at times. It's a beautiful movie. The soundtrack is also great.

It's not particularly easy to review though. Stalker is a movie about a, well, "stalker" who guides people into "The Zone", which is a place outside of their secure walls, where people go to find "The Room" which can grant anything your heart desires. He takes "writer" and "professor" and they stick by their code names, and all go through "the very complex maze full of death traps". Sometimes they don't believe in anything special about The Zone. Sometimes they do. Some things happen that can't be explained. It feels like a dreamy visual poem.
As for negatives, I never bought into The Zone as being real or having power from the first moment it was shown, and thinking Stalker was a kook. This was much before the movie itself suggested these things to me. It just seems like outside the walls, they haven't interacted with such a world in hundreds of years and thus attach metaphysical bullshit to things that are common to our own lives. Am I wrong? Well, the voice and cup may say I am. I still don't know. Also, some of the monologues do approach self indulgence at times.

Overall, the movie is just so beautiful visually that I can't help but give it a high score.