I have a model that I mirrored, and it had a logo. Obviously the logo also mirrored, and a regular contributor to the group here helped by removing the logo, and patching the face. Now i have to turn the mirrored part into a solid from the surfaces, and also have to cut the logo back into the face. So if anyone is bored, and wants to give it a try, let me know, I will send you the file.