Rifle Scopes : Scope for Hog Rifle

I think I have pretty much decided on the VX-R, now I'm trying to decide on the 3-9X50 or the 4-12X50.We are already killing a bunch of the hogs, but it's getting harder and harder for me to get the black crosshairs on a black hog's head when they're moving around under the feeder in the middle of the night, even with the kill lights. Age has surely caught up with me. I'm sure the Firedot Duplex would be a huge help. Thanks for the help so far and any more suggestions or ideas are welcome.