Hey - Sound quality is ok for youtube, but generally the limitations with that format make audio critiques difficult. I'm never sure how much of what I'm hearing is the mix and how much is the format itself, y'know?
The vocals are full and clear and sit pretty well with the music from what I can tell (zero experience with this genre). Performance-wise, I thought it was pretty strong. Is it possible though that you (or the first singer/rapper if other than yourself) sacrificed some of the flow for the sake of being careful with diction? It's not bad or anything and I'm not an expert, but it just sounded kind of careful and safe. The second singer sounded more relaxed to me which imparted more personality to the performance.
I'm probably just nit picking and looking for something to say here, as I certainly couldn't do something like this myself, so what do I know? Overall a nice punchy mix.