GITS had got everything to be fun, but it lacks something only the fans could compensate.
As for the technical stuff, GITS: Stand Alone Complex is professionally made indeed. The original anime was set in a near future, and the world you are to explore feels real and convincing as that can be. Both graphics and soundtrack help to make you feel like you were to bump into Will Smith on "I, robot". In fact, soundtrack often feels so industrial that it comes to be awfully annoying. You might want to turn it off most of the game; be sure: you're not missing much. On the other hand, at least graphically GITS: Stand Alone Complex is just fine, even though it may get a little monotonous here and there. You know, like desolate landscapes, not so colorful or eye-catching as they could be. However the game isn't so long for you to get too bored.
The story is told on in-game context boxes; the thing is, while you are shooting and dodging desperately across a room full of angry robots, you don't really notice those popping messages, in such a way that you'll need more than once to access the "Communication Log Menu" if you want to know what is happening at the moment. Also, the story is often somewhat confusing and, since the voice messages you get are hardly ever essential to your progress, you might not want to listen to them. Maybe watching to the GITS series could help solving that issue -- I'm not sure about it, though; I didn't follow the series to the end --, but if you didn't watch it, the game doesn't make much of an effort to explain itself.
The tips and voice emails your HQ sends you, as previously mentioned, won't matter a big deal; you will get stuck on the same stage not because you have no idea of what you should do, but because of the game's mechanics: you can't or at least don't know how to do it. Those mechanics work fine most of the time, but when it come to hop and hop onto walls (almost like Prince of Persia used to do, which is pretty fun for start), you'll find yourself repeating the same sequences over and over again in the case you just fall off during one of them... I say that without mentioning the difficulty level, which can come to be quite frustrating sometimes, especially when there's a sniper around; and believe me, you will almost certainly get shot in the head at least a couple of times, already on the first stage!
What else could I say? The game is kind of short, I was able to finish it on three days, playing three or four hours a day. There isn't much to make you want to replay the game either. You might find the multiplayer mode fun once you have unlocked the extra characters, but if you are alone, you'll most likely fight the final stage only once or even twice after beating the game the first time, but that's all.
Finally, GITS: Stand Alone Complex is a good game, despite the fact of not being particularly fun or entertaining. The fans of the anime will probably enjoy controlling their favorite characters, but if you're playing just for curiosity, you should look for a most interesting adventure. I would say that Ghost in the Shell had got everything to be fun: a solid fighting system, an interesting set of new features (like the evade moves Motoko can do), well-made scenarios and a plot with a lot of potential... But it lacks something only the fans could compensate, and that something takes most of the fun away.