Hello 
I am modeling, and texturing a character at the moment. Please tell me, what you think. Critiques are welcome.
pretty good, and the topology is certainly nice and even, but imo, his shoulders are too far forward, and too high, which makes him look tense.
As was said above the loops look pretty clean. There are some very stretched-out quads at the ankles that might give you trouble in animation.
The transition from his neck to his head is pretty harsh. Also his torso is quite rigid. You might squeeze his waist in a bit in order to better define his hips and ribcage, and push his mid-back forward so as to follow the curvature of his spine.