What ever is most comfortable for you.. but be sure and practice that way also. I do not put my finger in that small hole on the trigger guard. In a awkward shooting position, I would be more worried about recoil and the effect it could have on my finger when the gun might kick back. Also if I need to do a shot in the winter, what if my gloved hand does not fit in that hole? I just over grab the trigger guard. Again, this is my personal preference and has no indication on how you hold and shoot.

Everyone has different styles of holding the gun. My style varies from gun to gun actually. So if it feels right to you, then do it and practice that way. When the time comes out in the field to make that final shot, then do what comes natural and make your shot count.