I like the strong contrast between the cool colors of the dragons and the red in the background. The fact that the background colors do not blend smoothly makes for a nice effect and really adds to the piece. I feel like you could interpret it as clouds during sunset, or the glow of a fire set by the dragons.
I like the presence of different patterns on the tails and would have loved to see that extended further up the body. The differences in the heads is also nice. They look like they could be siblings without being mirrors of each other.
The one part that confuses me is how they are perched. There doesn't seem to be evidence of any feet gripping the branches.