RE: Opinion on hog calls
I've seen video of the squealer call being used and it was effective at calling in sows. The caller was imitating the distress sounds of a pig and the sows were just charging right in to the call with destruction on their agenda!
I've also seen video of the grunt call being used. The key to using the grunt call was to keep at it for up to an hour. The pigs that responded didn't come raging in, they were more like feeding in to the sounds.