If you just want more of the same, go ahead, try it.
Perseus Mandate has you taking control of another pointman in another F.E.A.R. team. The story runs parallel with the events from F.E.A.R. and Extraction Point, and ignores whatever plotlines were introduced from the two games. Instead, the game carves out its own story, one that is uninteresting, poorly presented, and eerily familiar. The better half of Perseus has you chasing a supposedly bad dude, much like how you chased after Paxton Fettel from the original. Alma, the creepy girl, and Paxton are barely in the game, and their connections with the new pointman are practically non-existent and makes Perseus feel unnecessary. All it does is complicate F.E.A.R.'s story. Also, some of the scripted story sequences aren't presented well, thanks to mediocre animation in these moments.
The gunplay, on the other hand, has remained intact. This time you go against some mercenaries with their own agenda, which are basically the replica soldiers from the past games except these new guys have goofy voices. There are a few enemy types, and the best one being the Nightcrawlers, which are much like the assassins from Half-Life 1. These guys are fast, deadly and can take around an inhuman amount of rounds before they're dead. The new weapons don't make them much easier to kill, but they're fun to use. The neat lightning gun is cool, but the limited ammo makes it practically useless. On the other hand, the new scope-mounted sub-machine gun will become and integral part of your arsenal, and is great addition. That's about it as far is anything new is concerned. The AI is still ruthless, but some of their cool actions like knocking down objects for cover are noticeably absent. The guns still feel fantastic, and the way the environment and enemies react to your shots are still visually impressive, if not dazzling.
The problem is that this has all been done before. The level design still lacks variety and if you've played the previous F.E.A.R. games, you'll swear TimeGate just ripped levels from previous games and pasted them onto Perseus. The scare sequences aren't very effective this time around because they've been done before and lacks any relevance due to the story. You see Paxton disappear into ashes in the distance, but so what? Why should you care? Unfortunately, you don't and therefore much of the "scary" sequences feel arbitrary and don't leave much of an impact.
A possibly bigger problem is how badly F.E.A.R's engine has aged. The game starts off outdoors, and it looks downright awful. Instead of utilizing the engine's strengths, namely its lighting and shadow capabilities, TimeGate tries to push the engine to do what it can't pull off. Even when TimeGate comes to its senses, the game is still way behind curve, graphically. Some of the animations are laughably bad, and will easily take you out of the game. The only thing that remains impressive are the fireworks show of particles effects, which can be downright awe-inspiring even after all these years. The aural component is still great, fortunately. Audio has been one of series greatest strengths, and Perseus continues that tradition. The new music is very well done, the voice acting is generally great, and the ambient sounds gel naturally with the environment. Besides the goofy merc voices, Perseus doesn't disappoint in the audio front.
After you finish the game, which shouldn't take very long (5-6 hours), new bonus missions open. Oddly enough, the bonus missions offer up the best firefights in the entire game. So if anything, play through the single-player for those. The multi-player is the same thing that's been free for the past year. It used to be that F.E.A.R. was a step ahead of most of its competition. Two years later and it hasn't done anything to maintain that lead. Still, Perseus Mandate is a decent game, and one that newcomers to the series should try out. The nearly stand-alone story means that you won't need to know much of what has happened in the previous games, and the combat is still something worth experiencing.