As long as you know that this game is based around one mission, you shouldn't be disappointed. You can make it as long or short as you want to. It really is remarkable how many options you have when it comes down to the mission. Great primer to get me excited for the game.
Guess I should of checked the reviews, I use to be a fan of this game series but wow has it gone downhill. Don't get me wrong game play is good but if your going to make a game with one mission and 4 tiny little missions just make it digital and don't waste time on making a disc. Not worth the rental at all very disappointing.
As other reviews have stated, this game is really short. The whole game takes place on only one level. Depending on the side ops mission, the time of the day changes, the enemy spawn locations are different, but it's the same level at all times.
With that out of the way, the game play was fun and enjoyable. If you enjoy getting achievements, this is an easy 950-1000 points. Going for the achievements makes you play the game differently which adds replay value. This game is definitely not a buy, but it is a solid 1-2 day rental. I'm glad i played it.