Quick update: I'm 4.5 hours into Metro 2033 (original, not Redux). First impressions:
-I'm not a huge fan of the save points. Sometimes I have less than 15 minutes of play time, and it sucks to have to restart at a previous checkpoint if I have to exit the game before I reach the next one. I feel like my 4.5 hours of play time should actually be 4 hrs or less due to this.
-the performance is terrible. Not sure if the game was not coded well or what. Framerates are actually not bad, there's just these jarring pauses and stutters that happen even while framerates are >60. It gets a little better when I disable 4x AA. For reference, Wolfenstein: The Old Blood played beautifully on my system. Google 'Metro 2033 stuttering' for many other complaints about this. One thing I haven't tried yet is setting the game priority to realtime in Task Manager. That seemed to work for some people. Oh, my system: i5-4590, 8GB, GTX 750Ti, SSD. Should be more than enough to play a 2010 game maxed out.
-I'm playing the Steam version that was a temporary giveaway a couple of months back, and almost every time I launch the game, it shuts down, then makes me launch the game in safe mode the next time (and I have to re-set the Video settings). Again, a common problem if you Google around. I have found that shutting Steam down before launching the game helps, not 100% but it does allow the game to launch normally more often. Someone suggested reinstalling Physx, but that didn't help me. I'm just living with it.
-despite all this, I'm still really enjoying the game! It's a good pace for me. I'm not highly skilled in FPS games...I prefer the story-driven cut scenes and stealth play style to running and gunning. It's very immersive and believable. The way the world is physically portrayed is beautiful and realistic. I feel like I'm actually wandering through a post-apocalyptic Russia.
On the RPG side, I'm 20.5 hrs into Pillars of Eternity. Really enjoying it, though it's going pretty slowly. I just reached Raedric's Hold, which seems to be about 2/3 through Act I. My biggest complaint (same with Baldur's Gate) is the real-time with pause combat. I find it a bit cumbersome, especially with spell-casters. I've found myself just letting the Auto AI do most of the fighting, with me pausing and re-issuing commands occasionally. Story is great, artwork is gorgeous, and the characters are memorable. It's definitely worth my time.
edit: setting metro2033.exe priority to realtime makes a huge difference. Turned details back to max including 4x AA and the stuttering is still gone while FPS stays at and above 60.