Let me start off by saying I didn't love, like, dislike, or hate Scourge. It left me with a very indifferent feeling.
Let's start with the pros. The concept behind Scourge is really cool and almost a fun idea. The effects and camera-work were well done. Some scenes were especially better than others (For example a scene in a mall involving an "infected").
Here are the cons. The acting is wooden and it's hard to get into the story when your characters take dramatic pauses after they say something that's supposed to keep you in suspense. The acting was especially horrid from the ladies in this movie. The story never get's as exciting as it should be because the script is so boring it leaves you wanting to watch an action packed movie as opposed to a slow-burn psychological horror. It tried to be a gory and action packed horror movie that was also psychological and slow burn which in my opinion failed because the two styles clashed.
I'd say skip it if you see it at stores and pick something up you'll know you'll enjoy. Even though it's technically sound it can't save awful actors and a lifeless script. Wait for it's syfy run.