Just finished Metro 2033. Overall a fantastic game. Superb atmosphere and solid story and gameplay. As an adaptation it was okay, wasn't too fond of the heavy action sequences as it's very little action in the book, and the story went a little too fast at times.
For example, the arrival at Polis, which is the main objective for Artyom and a huge part of the novel, was done in like 5 minutes, which I thought was strange. Also, the different stations you visit, which plays a big part in fleshing out the lore, was mainly just used as a place for stocking up ammo.
It was clear that 4A games tried for a more action-focused approach with big battles against the various monsters and nasty humans you encounter throughout the adventure, than the more somber, tense filled and psychological journey that takes place in the book. But I know, video games gotta video game so in the end, I'm not too surprised that the the developers went this way. Different mediums and all that. On the positive note, some sections were very faithful to the novel and overall 4A paid a great amount of respect to the source material.
I enjoyed this game a lot. Terrific work on the port, it looks amazing with no frame drops whatsoever. It's precisely the game that the Switch needs to diversify its library of games.
Metro 2033 is the best story-focused FPS I've played since Alien Isolation and Metroid Prime, and that's not a small feat to be compared to those two behemoths.