For a F3 fan (like me) this is an instant purchase, but others may need to consider.
Since this is an expansion to the base game, I will only review the story, loot and gameplay.
the Story, or lack thereof is nice, but pretty insignificant. you don't get much of it, and it kinda just tells you to "KILL COMMIES!". but hey, I ain't complaining, I didn't buy and action based war expansion for story purposes.
But before you enter the simulation, you're story is, in a nutshell: you find a strange radio signal requesting help to anyone who can hear the signal. The strange part is, you can only hear it because you have the pip-boy, which brings you incentive to go check it out. you end up at an Outcast outpost, and they ask you to enter this simulation because they believe there is some serious lootage beyond a locked door they cant get through. So yeah, they put you in a life threatening situation for armor and guns. yay. But you do get a share of the loot.
The loot, is nonexistent. Until you finish the simulation, that is. when you're in the simulation, all the enemies dissipate into a series of blue binary code. Boxes, also are out of the question. but it makes since, because it IS a simulation.
the gameplay is pretty sweet, but is a little weak. Its more action based and fast paced, so all your weapons are given to you and their are health and ammo dispensers (bye bye stimpacks =[ ) everywhere. The gameplay takes an interesting turn, giving you a squad to hang out with, even though they don't do a dam thing half the time. The leader of the squad (besides you) is surprisingly helpful, but everyone is kind of a bullet sponge.
There are some extremely interesting enemies, including the first vehicle encounter in fallout 3. Its called a chimera tank, and it will MURDER your face off. But its a fun battle, nonetheless. Also: possibly the most interesting enemy in fallout 3 history are the Dragoon stealth units (or something of the like) . what make them so interesting is that they are invisible. Yes, it looks like these ninjas got hooked up with a couple stealth boys. Alas, it is the suit they are wearing that makes them invisible, and once you shoot them, you can take a good look at it. Its like a super ninja suit OF DOOM.
That pretty much sums up the gameplay, you can choose your squad (I suggest 2 infantryman) to go into battle, and towards the end, there is a decently epic battle and its kind of cool to see the prototype power armor in action.
After you beat the simulation, you cant go back. Which sucks. Hard. You have to load up a save to do it again, but its not really worth it, unless you simply want the loot.
Ah yes, the loot. Remember that stealth armor? Its yours. Along with this bada$$ weapon called the Gauss Rifle that runs on micro fusion cells and is even more powerful than the Alien blaster! You also get the sword og the general of the Chinese army, which comes complete with some serious shock damage. And last but not least, come the prototype Alaskan power armor. Awesome. It doesnt have as many perks as the regular power armors, but it has +25 rad resistance, so its worth lugging around.
Overall, its worth a purchase, and a playthrough, sadly, you will just forget about it just as quickly as you finished it. worth ten bucks? yeah. why not? At least its not horse armor.