Hey R4R here ^_^
I'm a big fan of Dubstep, (My first time doing a critical review of music so bare with me)
I am a big fan of a lot of the things you did in this song. I'm a producer myself and Learning to produce alone only looking at youtube videos I can see alot of technique in your song especially in the mastering and engineering section when introducing instruments and new sections. I see you got the Side chain down packed and using it to your advantage here very well. Like I said I'm a big fan of the genre and the different styles you expressed the Genre in this song.
The only reason I give you a 4.5 is cause I saw how you used your motif through out the song and, I know the idea is about generating that impending doom feeling and but if the Motif was a Character or a Conversation: As a Character it would be unwavering and Static because of its repetitiveness I know the background instrumentation did explore different emotions but I was actually expecting the Main motif explore different intensities and higher or lower expressions. But instead I got something Equally satisfying which was how dynamic and changing was the drums inside the Motif. I was able to Visualize and unchanging relentless Virus (Motif) Hovering over a population in panic (Drums) and thats what captured it for me to being better than a 4.