Rainbow Six: Vegas was the game that made me switch back to XP, at least for games.
Before playing Vegas, I was gaming on Vista. Vegas kept crashing at various points (which is very frustrating considering you can't save) so I pissed it off when Stalker came. So that means, unlike my previous game reviews, this game will be running on a fully capable, up-to-date XP Machine, not a dodgy, broken, stuttery Vista machine.

The World Awaits
The World Awaits

First off, the graphics are beautiful. The game looks awful in just about every screenshot I've seen of it, yet in motion it really does look amazing. The FMVs are also beautiful, and have an awesome style that really suits the game. I started off with a nice and smooth 80FPS, the lowest I got in the beginning area was around 40 during a fire-fight. However after a while it slowly started to decrease, and the average I get now is around 30. During hardcore fire-fight with lots of lighting and shit the lowest I got was around 12, and it didn't stay there for long. And I must say, by the way, whatever engine they're using has perfected dynamic lighting. This is the first game I can honestly say that I didn't lose a single frame when several guys all with flash-lights on their heads (mine included) ran through an underground area, their lights moving the shadows of the near-by objects around the room. Ace job, guys.
Sometimes the game appears to finish loading the level before it's actually finished loading the level. So I'm running around while it's still loading, bringing my FPS down to 2-5 while my CPU is furiously spinning away doing complex mathematical equations for a few minutes before finally settling back to normal. I'm not sure if this is related or not, but several times I've had enemies spawn in large groups right in front of me. I'll just be walking along minding my own business then suddenly the game stops for a second and the next thing I know there's 10 or 20 bandits all shooting at me, or a dozen or two wolves gnashing at my feet.
I booted in to Vista for shits and giggles to try this game, receiving a frame or two every other second. The most I got was eight at one point. Exact same settings as they were in XP. I don't think I'll be gaming in Vista for a long time.

The one thing this game lacks? Alternate methods of transportation. We're talking about a LARGE fuckin' world here. They expect me to walk everywhere. I can run, but I get easily exhausted, and every two minutes I have to stop to recover my energy. One of the big features of the game when it was in development was the vehicles. You could find jeeps and shit and drive them around the place. Oh God how that would help. Or at least some kind of quick-travel feature like Oblivion. But no. I need to walk everywhere. I got so sick of it I downloaded a trainer specifically for the unlimited run function.

gloomy post-apocalyptica
gloomy post-apocalyptica

The game is full of bugs. I've only been playing for a little over a day but I've already had to back-track a save twice because obscure bugs rendering my saves unplayable. The first time I loaded my game and I was stuck inside a wall. Clearly I didn't save there, at least I don't remember saving there, and there's no clipping cheat to get out of it as far as I can tell. The most recent time I saved inside a building, and one of the NPCs lodged itself in the only door leading out. This game isn't like Half-Life or Oblivion either, where NPCs will move out of your way if you push them around. No, this guy was quite content in blocking the only door out of the building. Several times throughout my game I've had to wait for NPCs to get out the way of doors.

Speaking of NPC bugs, the biggest and most frustrating bug this game has is the repeating voices bug.
Walk in to The Bar and you'll see exactly what I mean.

Guy 1: Get out of here, Stalker!
Guy 2: Why won't someone help me?
Guy 1: Get out of here, Stalker!
Guy 4: Don't just stand there, I said come in!
Guy 3: Psst! Come over here!
Guy 3: Hey! I've got some information you...
Guy 1: Get out of here, Stalker!
Guy 3: .. could benefit from!
Guy 2: Why won't someone help me?
Guy 3: Psst! Come over here!
Guy 4: Don't just stand there, I said come in!
Guy 4: Don't just stand there, I said come in!
Guy 1: Get out of here, Stalker!
Guy 4: Don't just stand there, I said come in!
Guy 4: Don't just stand there, I said come in!
Guy 4: Don't just stand there, I said come in!
Guy 2: Why won't someone help me?

If it weren't for the strong presence of enforcers I would kill them all.
Apparently there's a mod to fix this, but it's pretty lame that we have to rely on a mod to fix quite a considerably annoying issue.

When you decide to physicalise everything in the game, you're going to have the same problem Half-Life 2 has. Debris blocking you. Run along the road and hit some debris, and you're going to stop, or launch off the ground at mach-5 speeds. Sure that's understandable, I mean, how much debris could there be on the roads? Just wait until you start creeping around dungeons. There is shit everywhere. I've also managed to kill myself by running directly in to a barrel. I was running and I guess I hit some debris, which launched me in to the air a bit (1 or 2cm, nothing noticable), and when I hit the barrel it hurt me so much I died. Games have a long way to go before physics are perfected.

I've come across a not-so-unique bug. I can't finish the game properly. I can't get the "true" ending. You get the true ending by following the main quest, and then getting a triggered special quest "Find Guide", where you basically have to find a Stalker named Guide. I've searched around and I'm not alone, quite a lot of people have run in to this bug.
I believe my problem is that one of the main quests wasn't properly cleared. It was still in the "active quests" section of my PDA. The quest had me go down in to a sewer area and find a secret stash of stuff. After I did that I was supposed to exit the sewer, so I did, I went back the same way I came in, talked to the guys at the top and figured the quest was done. NOT SO! Apparently the game wanted me to go out a different way. I was supposed to go further in to the underground area, kill some more guys, kill a big mutant freak thing and then find the exit there. This wasn't told to me though, I only figured this out after exploring the sewers again later and finding the other exit. Upon exiting, sure enough "Task Complete!". Because I've done several other main storyline quests before properly finishing this one I can't get trigger the "Find Guide" quest.
I've actually had to figure a lot out on my own, things that weren't told to me at all throughout the game. Like what those flashy numbers mean under my radar. At first I thought it was some kind of radiation level indicater. It's a "contact" (other Stalkers) counter.

The church of DEATH
The church of DEATH

I don't think I've said one nice thing yet. The game area is massive, but a little repetitive. Wait. Nice! Think happy thoughts! What did I like about this game? It was entertaining. I think the bugs and issues really outweigh the good though. The biggest issue I have is really the method of travelling. And the fact that I keep getting random quests from people that I've never spoken to. I'll be walking along and then a giant "KILL BANDITS AT SOME CAMP OVER THERE" pops up and I have 1 Day to complete it or I FAIL it. Where the fuck is this camp and why do I care that bandits are attacking them? Furthermore, why do you assume I have time to help you defend you're stupid arse camp. If I don't do it I get a giant message flash on my screen "TASK FAILED!" like I just shot your dog or something. Like I care that you can't defend your stupid camp on your own. Speaking of warring camps, I find it cool that there are constant wars between rival groups. Like one time I was going past this building and there were several neutral Stalkers there, and when I come past the next day there's a heap of hostile ones that had apparently taken over the place. Another time I walked past the same place and saw the neutrals had taken over it again, and the hostiles were coming in to attack.

My final issue is the patches. A version 1.00000000000000000000000000000000000000000000000000000000001 patch has been released. It's a very minor patch, according to the version number, yet if I apply this patch, every save I have with the retail version (1.0) will be rendered obsolete and non-functional. Bravo!