Actually I agree with Dave and disagree with him, too. Image is vitally important, but image must reflect who you really are. I get sick of all these moody black-and-white photos of dirty unshaven lads beside railings or in front of graffiti-laden walls. They all look the same!
Motion Theory HAVE an image - it is intelligent, slightly eccentric and yes, a bit posh. They like tea. They don't swear every second word. They know what consonants are. That just makes them stand out from the crowd. And still they produce exciting, interesting, angry, amazing music.
I can't think of another band that does all this. THAT is a unique image, take it or leave it.