The slogan, "at the sign of the dot bomb" is used in the current logo because the letter "o" in com is replaced by a cartoon acme bomb. The slogan only makes sense if a bomb is used somewhere in the logo. Entry #12 uses it effectively but all other entries that use it don't have any bomb reference. So if there is no bomb then there should be no "at the sign of" strapline. Apologies if I that was not clear from the initial brief. As I said in the brief I am happy to see designs without bomb and strapline but its all or nothing. If you want to use the strapline you need a bomb. No bomb no strapline.
#67 looks very good. Nice and simple. The dog tags are a nice touch. The other two I don't like as much and this is not your fault as I did not make this point before, but imagery is fine but should have either a neutral or fantasy look. The tanks look too contemporary and our business is very heavily fantasy (futuristic or historic)