I would say 27-28 on the mainframe and 30-31 on the cheaters. My thought is that his ears look big because he doesn't look to be an older deer. Older big bodied bucks will have a bigger neck, a blockier body. Those characteristics make their ears look smaller and their eyes will look smaller, even though in reality they are as big or bigger than a younger lighter buck. He doesn't look that heavy, so I am guessing he is a younger deer just coming on. Also his antlers are not that weighty and haven't gained the mass yet.
Great deer any way you slice it.
ShadowHunter