If I could, I would have given this game 2.5/5 or 5/10. But considering that I bought it for $2.49 I'll round up to 3/5 because of the very good bang for the buck.
I did not find this game particularly frightening. The scary part of this game was mostly jump scares, and they were often not really dangerous. So after a short while I ended up with more or less just shrugging them off. I also found the story to be a bit weak: There was some phone answering messages that gave some information, and some computers with some information, and a "narrator" that told some stories. But there was also some parts of the story that did not seem to be followed up on and thereby leaving holes in the story.
The enemies is a bit monotonous with not much diversity, and they are a bit poorly distributed: For a while you do not encounter any enemies, and then suddenly you meet five or more at the same time! I made the mistake of playing through the game at the second hardest difficulty, and especially towards the very end of "Perseus Mandate" the difficulty is ridiculously high compared to the rest of the game.
There is a big bug in the game that makes the game freeze and display the message "Disconnected from server". This can probably be fixed by reducing Texture Resolution to medium or lower.
The game can be played in 1920*1080 or higher if you start the game, adjust settings, and then edits the settings.cfg file for the game in the C: drive. Note that the settings will be reset if you enter the settings with the resolution after editing the .cfg-file under the folder TimeGate Studios/Monolith Productions depending on what part of the game you play. It might be smart to use Pixel Doubling if the game stutters and/or reduce visual settings.
All in all: If you like older games and you get this game at a reduced price, it will give you many hours of entertainment for a low price. The game is not bad, so it might also be a bargain for you at full price.