If you really, really dislike the idea of anthropomorphic cybernetic animals then Vivisector may very well be the game for you. You're literally blowing apart these creatures for the most part of the game.
Vivisector clearly takes a cue from Soldier of Fortune and includes damage modelling that ensures every enemy you encounter won't be getting an open casket funeral. However, unlike Soldier of Fortune, these beasts may well carry on the fight even after you've removed their face with some buckshot.
The most defining influence is unmistakably The Island of Doctor Moreau. But it's not such an overwhelming influence on this game that it's in any danger of making sense. For instance, human soldiers will attack you, despite the fact that you're both supposed to be fighting the cyberfurries. Yet others won't, despite being on the same side as those that do. Going so far as to make demands of you as soon as you meet them. There are other inconsistencies that don't make sense, but I post spoilers here.
There is also an attempt to distinguish the game with an ability to upgrade some of your abilities as you progress through the game. You can increase your speed, health, endurance and accuracy. Points towards these upgrades can be earned through killing enemies in certain ways and / or a certain number of them in rapid succession. You also get points for finding secrets.
Although it runs well on Windows 7 64bit, there are some bugs in this game. Mostly physics based, such as ammo crates dropping out of the level. Sometimes enemies don't open up the way forward like they're supposed to and you have to start the level over. But don't worry too much about losing the ammo crates. In this game there's about three or four times the ammo and health you'll ever need to stay topped up at all times. Especially later on.
Probably the worst thing about the game is the opening few levels. It's as if the developers significantly improved during the development of the game as the gameplay improves throughout.
It's a shame therefore that they didn't go back to those early sections as they definitely leave you with a much more negative opinion of the game. Some of it really is very amateurish. Another thing is that you never need to reload your weapons. Given that this game was released eight years after Half-Life, that's a glaring omission
Those that loved Cryostasis and are looking at this previous effort by the developers as a potentially similar game I have to say don't bother. This is nothing like Cryostasis in terms of either quality or gameplay.
That said, I certainly don't regret buying it. But I might have done if it wasn't £1.50 at the time.