Personally, I think it looks better on a forum with a grey dark background. (This only pertains to people using a brightly colored background for their skin here.)

If I may suggest, as I've done the same thing in the past:

When doing transparent sigs such as this one, try to fade out every edge so that it doesn't have 'hard' edges clearly visible, and it rolls smoothly with the background it is placed in, regardless of the background.

Here's a little something to compare with, from the forgotten depths of my Photobucket account:

Such as this or is there a specific technique to doing that?

Edit: ... Which looks like SHIT on the Dragon skin.

What I meant was, take a round eraser brush at low hardness, and erase around the edges of the sig until there is no 'solid edge'. On the second sig I posted, you'll notice at the bottom there is still an 'edge' there, while on the first it fades into the background.