Looks rad! Maybe put a little more color into the metal from oiling, etc. ala From: http://www.polycount.com/forum/showthread.php?t=89830 Also, make your spec work a little harder! I really wanna see a lot more of the scratching, dirt and grime in the spec more than the diffuse. I think that'll give the metal a lot more…
I had it in there, but marmoset didn't like the transparency. Here's a screenshot without hitting the render output Thanks for the comments so far, still working on tweaking the spec map
I agree with what dim is saying here. The diffuse is looking, great, the bake is killer, but the spec is certainly lacking at the moment. A better lighting setup would help this out as well. Try and get some rim light all up in there.