For a speed study it really is a good job, you can actually appreciate the details although because it's a speed study they are blurred. The blurriness actually adds a unique touch to the picture. I really would like to see the ending result if you ever decide to redo it. I also like your other work, it's very interesting.
your artwork was featured here: [link] you say you're not very happy with the resulting in this art, but i think it's pretty fantastic. you did really well with the facial structure and lining. the colors are complimentary. i love this