[spaghetti]

foxfish is right: standing is easier, you feel safer and more comfortable with your foot on a solid surface while loading such a big and powerful gun. So if you normally dive in shallow you'd better do it this way.
But if you spear in deep waters (as I guessed you do with a 110) you'd better get also familiar to load it in the other way.
Enjoy your spearing (me tomorrow after a looong "dry" week)