Go out and buy a copy of the damn game! I don’t think it’ll beat out Half-life 2 in terms of gameplay, but I highly doubt you’ll feel as though you wasted your money. Obviously you won’t be able to run it with the highest graphical settings (I sure can’t), but that won’t detract as much as you probably think from the game. The settings are nicely scalable. Just make sure you have a nice graphics card.
A couple points:
The interface is really well done. If you walk up to a computer screen your crosshairs turns into a cursor and you can fully use the computer screen. For example, when typing in numbers on the keypad a separate “keypad screen” doesn’t have to pop up as is standard in so many games. Rather, you manipulate it right from the normal 3d view. Ehh, I’m not explaining that very well, but you’ll see what I mean.
Some parts of the game are just excruciating. As you can imagine, most of the levels are very dark and sometimes the lights conveniently turn off (power failure?). Thus, often you are desperately in need of your flashlight. Unlike most games where you press the flashlight key and it turns on while you still hold your gun (what is it, a headlamp?), in D3 you have to switch to the flashlight using a quick switch button. It works very well. Basically you have to sacrifice holstering you weapon in order to pull out the flashlight and see what the hell is going on. Adds a lot to the scariness as you definitely feel vulnerable when you pull out that flashlight.
Again, I’m not very far into the game. Not long ago, I first received the Shotgun!