N3 is an entertaining game, but it certainly has flaws.
I downloaded the demo when it was released via Xbox Live back in the day, and what I tried then was somewhat OK, but I still felt like it lacked a lot. Although I was obviously wrong, I blamed it on the fact that the demo must've been limited.
Now, quite a while later, I bought this game to see if I had been wrong, or if this game just wasn't worth it. Trust me, it's not worth it.
The first thing that really annoys me about N3, is the voice acting, which sounds like it was done with a complete lack of enthusiasm and interest. The voices sound completely fake, some too high-pitched, and none of the actors even sound remotely interested in trying to do a good job. This ruins a lot for me, since bad voice acting is even worse than dated graphics.
The gameplay in itself is OK. You see a lot of badguys, you get to kill a lot of badguys, and on top of that, you can execute awesome combos.
A problem here, is that the normal basic attacks will get you just as far, if not further, than the big flashy combos and special moves. You don't need the specials to even complete the game, in many ways it will only halt your progress.
The visuals were good for the time when it was released, but now it feels dated and not very detailed or good. I won't comment a lot on this now since I obviously can't compare them to the games released today, but I at least find them kind of boring. Any form of graphical violence is stripped, you hear moderate "thud" sounds when you hit your opponents, and they just fall over with no visual damage.
Now, I'm not a big fan of unnecessary violence, but if you're supposed to slaughter thousands of thousands of enemies for 10 hours, you might aswell try to make that look and sound a bit better to be honest.
The sound effects are fair, with the exception of most combat effects (which is kind of what the whole game is about). The music never really gets boring but neither does it stand out. It's more neutral and just there.
To sum up, if you find this game for 20$ or less, I guess it would be worth the money if you desperately need a hack and slash game to vent out your frustration. But check out the demo first, before you go on buying it. You might find it not worth your time, just like I did.