I filled it this evening and yes it fills all four holes and doesn't spill out. The girls haven't used it yet though my fear is that they keep pulling food out onto the ground and empty it onto the ground. I'll have to wait to see. In order for it to spill out from the holes on the ends like you mention it would have to have enough force to fill the whole horizontal tube, or have them holes located directly under the hoppers.
My plan was to put crumbles in one side and then scratch in the shorter side, and i still may do that but I also thought it would hold more food than it does, my calculations were way off for volume.
Thanks for your reply.