Not bad, not bad...
I feel the dubstep overall could be enhanced better by making it more dynamic in rhythm.
Extending a bit beyond 1/4 time, nothing too much.
One fo the things that makes a dubstep great is not just the dubstep itself, but how it interacts with the rest of the song and maybe even extra elements to spice it up.
Now the actual DBSP parts here could have been a bit more consistent but that I care less about.
Otherwise, I can rock w/ this.