Thanks, Rebecca.
This is the kind of comments I really need. Very informative and helpful.
[i]>>But I think the thing which both you and Slux need to work on is loosening up a bit, and getting something of the gesture in your drawings. You are both technically really good, but you should try to give your drawings more of a sense of life by using more fluid and loose lines ~ not to say inaccurate lines, but lines which ‘breathe’.<<
[/i] Yeah, I absolutely understand what you mean and I am not satisfied with my drawing. I can see that absence in my drawing(s). It looks too “syntetic”. Actually it will be next step to improve my drawing skills to that level. When I´m drawing I also feel that - no fluid lines, no ´breathe´ and therefore the process is not so entertaining like it should be.
Actually I am just not good at drawing at all, maybe some of my drawings may look good but this is nothing compared to drawings from really good artists. These also took pretty much time to draw (and this is another evidence that I draw too slow and without flow). I guess it will take some next hundreds of drawings to be able draw fluid lines but I´ll try to jump in and try it in my next drawings.
Now I´m earning money for new computer (for recently bought Maya) so I have almost no time to draw, but soon I want to start my self-study and I plan to draw as often as possible like Slux and many others here do now. Reminds me I could also start some anatomy thread - this is great option here.
I also want to jump in sculpting and 3D, so I can´t wait to the moment when I will have necessary equipment and start doing this all artistic stuff. It will be fun.
See ya 
You have some nice work with the shading here, although I’ve also seen you do even better shading in other pieces. I think given the short amount of time, you have done a really nice job with this piece. 