It was a decent FPS. However, it just didn't feel like Halo. It wasn't just the lack of Master Chief, but also the stupid visor and the ugly view the whole game.
I finished the campaign in around 6 hours. The story is decent and the voice acting pretty good. It could be a good value if you want all of the Halo 3 Multiplayer on the cheap (included with purchase....not with rent from Gamefly).
1) good controls
2) fun weapons
1) ugly visor view through the game
2) graphics were not that great
3) just didn't feel like Halo