Personally I'd choose the one on the left, I'm not sure why, I just prefer that one. Also, I'd suggest that you actually set up a signature properly, to do this go to User CP, and then select 'Edit Signature' in the right hand column. This way you won't waste time on each post by redoing your signature.
Lulz i did the third one. Thats what gets my vote All i did was add an overwhelming red tint, then the sharpest C4D i could find about three times over. I spent no time at all on that lol.