Pretty good stuff...
Well, this is obviously very well produced. The music is very clean sounding, and it serves as a very good background to the vocals. I think the music is a bit bland and generic, but then I don't really listen to a lot of hip hop and I'm really not qualified to say whether or not the music is much better or worse than the average track in the genre. It got a bit repetitive though, and I didn't miss much listening the first time through, as I didn't find anything new upon the second.
The vocals were very, very well performed, both by you and by your friend. What I heard of the lyrics, however, didn't really stand out to me as amazing, but perhaps I just missed the message of the track, and I really don't think I'm the intended audience here. Again, can't really be sure because I didn't discern all of it.
So what you have here is a very laid back, groovy sounding track, and that's perfectly fine. It's just not really my type of music, I guess, and I thought it could use some excitement.
Still, you're obviously a very skilled and experienced producer, which is admirable. Keep it up.
If you get the time, could you listen to and review my newest song, "A Night Underground"? I'd really appreciate it, thanks.