I have not personally had too much luck calling Hogs with hog vocalizations although I know some who do. Now I have called several hogs using baby rabbit sounds but that's out of many stands so not a high percentage strategy. If I was focused on shooting hogs I would probably try calling more but they just seem to show up all the time when I am busy hunting coyotes so most times I just ignore them.
It works but you have to know where they bed down. I've had about a 50% success rate calling them. Meaning, half the trips I've tried it I have called one in (not 50% of the stands I make). That being said it's almost always a big, nasty, rough looking boar who has obviously been fighting. They typically have scars or cuts on them from defending territory. It can be pretty intense. If you look at the mesquite tree at the top left when the video starts you can see my Hellfire. Sound was Boar Sparring.