Eminently playable, riveting, hilarious. The only major drawback is a lack of guiding the player toward the mission goal
The best highlight of the game are the cinematic cutscenes and "overheard" conversations. The voice acting, musical score and scripted scenes really make the game. The story line is continuous and consistent, and plays much like a movie - the influence of Fox Studios definitely shows. Throughout the game, the player hears conversations betweem guards and other characters, some of which are useful to complete the game, and others hilarious additions to the story line.
A few words about the graphics - even for the date of release, the graphics were somewhat dated (the engine for the sequel fixed this.) Character speech looks particularly awful, and this is especiallly noticable in relation to today's games. This does not, however, significantly detract from the game play. In this case, immersion comes from interest in the story line rather than impressive graphics - the mark of an all-time great game.
This game is long. The first time, I spent at least 40 hours playing to the end. Also, there is significant challenge in replaying with increased difficulty levels. Another replay consideration is that items "earned" late in the game can be selected when replaying earlier missions. For instance there is a level where an area is unreachable the first time because of the lack of a piece of equipment you earn later.
My biggest complaint is the lack of guidance in several situations. Finishing the mission goals in some places opens a gate which require you to backtrack depending on the path you have taken. While I do not necessarily want to be "herded" down a linear path, it is frustrating to spend 10 minutes or more looking for an exit you saw closed before.
Overall, if you want an entertaining, immersive experience with great replay value, this game is a must.