The C-14 has always come from the factory with an AGM absorbed glass mat battery. AGM batteries have no overflow tube or openings for liquid. They can be shipped USPS because they are not liquid and can be stored upside down without leaking. I would never put a liquid acid battery on a motorcycle again given the choice, the acid overflow tube can be accidentally knocked off and the acid removes all paint on the frame below. And if the tube does ever work as planned, the acid coming out of it will be slung from the back tire onto everything nearby.
I use the MBTX12U Battery. 14 Amp, 200CCA AGM. Available at amazon, ebay, even sears. I paid about $80. They are yellow, have two extra connections for accessories. And they have threaded holes in the connections for direct bolting, instead of that old square nut balancing act that you have to do with the Scorpion or Yuasa, blindly trying to lift up/place the nut while turning the bolt, dropping the nut into the frame lost forever, where do you buy square nuts? Why would you put up with that?