I think there's too many variables at play here. Are you a natural heavy weight?. If you can hold 205 naturally and feel better there I'd say stay there. I'm a natural 250 +/- however I fight better at about 220lbs, but it kills me to stay down there. As soon as a lift heavy again I gain weight very quickly.

Like I said, too many variables come into play. Like your opponent etc. I wish I could stay at 220lbs, but can't