So far, I think it's a good game.
It's sortof a Fallout meets Deus Ex and watered down a bit.
It's definitely buggy as heck, but since one of my other Favourite Games of All Time (Planescape: Torment) was also a buggy-as-hell program, I can forgive it
One thing I wish this had was a co-op multiplayer mode; The scope for exploration the first time you play it is immense - I can't remember the last game I played where I could just wander and trip over cool stuff or run into scary bitey things that need a good shooting.
It is a damn hard game; The number of times I've run into some scary beast or random merc team, then run away only to end up in the middle of a Whirlygig field in my haste... ugh... thank smeg for saves.
The little touches are what make it for me in this game. The way the other stalkers will gather to 'safe' areas during the night, and how you can randomly come across a couple of factions fighting each other. That thing with the local wildlife scavenging corpses is another great touch, and there's the famous guitar-playing russians. (I wish I could understand what they are talking about around the camp fires!)
It does feel like they went for the little touches at the expense of the whole, but y'know what, I like that. Most games these days are the opposite - Solid, but lacking in... I dunno... depth? Immersion?
I'm glad I got it. The fact that it works in Windows 2000 is a plus (Gas Powered Games and EA are on my HATE INTENSELY list for making SupCom and C&C3 Xp-only for no good reason!!!