I'm assuming we talking about extremes here... would I rather have an extreme round large butt, or an extremely flat ass?
Look man, I'm not trying to see a chicks tailbone in doggystyle. If a womans ass is round, there's hope for her no matter how big it is. Even if she loses weight, that ass will still be round. If she got a flat ass, the only thing she can hope for is big ass tits to make up for it. Usually girls with nice round bubble butts don't have big round natural tits to match, and vice versa, but breast implants are way, way, way, more acceptable than ass implants.
Anyone voting for flat, dumpy ass is sick.