saint, i definitely dont think its your best work by a long shot. Take this as constructive criticism, cause I'm definitely not saying your work sucks, i just know, by your website and a few conversations with you, that you can do much much better. The font looks too stoney, these are supposed to be fast, modern cars, not something from 400BC. I'm sorry, I dont have a font off the top of my head to suggest to you, but not that one.
Texture the background some, blend the cars in somewhat so they dont just look copy and pasted, and find some other shots of them so they're not so static.
If you were asking about your sig on the other hand... it looks incredible