I like dark effects, but theese ones are too dark, you can barely see any details at all. and a little bit more color wouldn't hurt. The renders in your sigs seem to look really cool when they're light, you shouldn't make them unvisible. I like the font, but maybe you should do something more with the text, it looks too plain,.. why did you type the same text twice?. the border looks a little bit too clean to me, but it's not bad.. try lighten up your sigs, I think that will make them look better. And something like a character or somehting would look bad eighter. Still, you have done a good job. did you make the renders yourself? keep it up