<--- for some stupid reason, I did not save this as an .xcf file before I closed it, so I can't make changes to it :( Yeah, the font is wrong and her hand is messed up. Sue me. >.> CnC please thanks :)
Lulu sig is pretty good. I would suggest fixing your light source. Make the transition from the white light to the dark background much less defined (more spread out). Get rid of the faint white-light-things in the top right and far left side, also. It bothers me. lol Not much to say bout the other thing. Cool I guess.
I like 'em both, especially the sig. The only thing is if at all possible maybe get rid of the "target" logo in the corner? :P doubt that was intentional, but I look at it and think "target...?" Other than that, I love the sig :D very cool
The C4D use is pretty nice, but it's a little overkill. Add some negative space on the left and use the burn tool (not sure what it is in GIMP) near the left. The two light sources kind of throws off of the whole thing a little. It's not bad, actually, but tone down the bottom one just a tad. Maybe use a large soft brush and just tap and lower the opacity.
sig1: pretty good but i think you used too much C4D's and on the light source tone the brightness done a little bit, over all pretty good 8/10 sig2: really got no CnC for it, Pretty Cool just change the font from sans 21