Very nice, the battle horns/helmet looks really blurry, if you want to go for the water color effect with clean lines then go for it, but if you want to go for clean clean then stick to it.
The style is very Gundom. Its nice how the character has a antenna on the his back (witch could be for communicating?)
How about a more distinctive eye?
If only we saw more of the feet in this piece of art it would be better.
The position your character is holding the gun is very natural and dose not look awkward.