I had the first game since I was a little kid. I remember trying to play through the first game with my dad, but the intro was a tad too loud and I never touched the game again. (I was two, give me a break!) Anyhow, years later, I saw the games played through on Youtube. Instantly regretting not having this series, I bought all three games. The first two refused to install on my XP machine. I gave them to a friend, and he still has them, managing to install them in Windows 7. Now that I have Windows 7, I have yet to get my games back, but even if I did, I doubt that they work too well. It is unfortunate that I must report not to buy this game if you are running Vista or Windows 7, as there is an issue still pending in the community regarding the fact that the game CRASHES WHEN I TRY TO SAVE OR LOAD! Nevertheless, I feel that this is the best game in the series, and if you can get either a copy of XP or a virtual machine running XP, give this game a go. Who knows? You may actually beat it!
A complaint about the game itself: Because of the nature of navigation, it can occasionally be tough trying to get from point A to point B. Its difficult to understand without playing it, though. Its especially tough in one part where you have a limited O2 supply. The only reason I have to consult walkthroughs is for directions, not puzzles. (Except that one in the space station. Get through that maze in the docking bay with no help. I DARE you.)
All that being said, wait until the issue is fixed to purchase. Unless you have XP. Then, go grab this game, the strongest in the trilogy!