It's is a decent sig but there is too much going on all at once. I really like the font a lot. The render is a good choice but like I said, the background has too much going on. I'll rate this 8.5/10.
the flow is all off, in fact, there is no real flow, even though that render has such potential. the lighting is nowhere in specific with no focal congregation (sp?) of the light. Your render needs to be brought into the sig more, and not just look like it's slapped on top like it does now, really make us feel like he belongs there, he NEEDS to belong in there. The text is great, nothing i can see at fault with it.
It's really not that good to be honest. Like the previous poster said there is no flow.
The colors don't match and you made no effort in the background.
But you have great potential, good luck.