I don't like the header, in this sort of design, i needs to be eye-catching, and although you've used nice 3D render, I don't see why it's necessary? And again, MAKE A LOGO!
You're designs are all well done, some very well done, but you MUST use more original thoughts, throw in those little extras that will take your designs another step forward.
But overall, another well done design
P.S. Am I the only person on these forums critting? Lol