Which has better gas mileage? Honda CBR or Honda Shadow Aero?

I'm looking at getting a motorcycle, have been for a long time. Gas mileage is a big factor right now. I don't want a scooter or moped or anything, still want a bike, and my local Honda shop has the best prices when it comes to... Everything. So which Honda motorcycle (at least around 600 cc) is going to get me best mpg?