The SHIELD is a thick layer of tough ass skin (I assume)that builds upover time, b/c the hogs fight with their tusks (teeth) and the sheild protects them when they are fighting with other hogs and it pretty much covers the vitals. I shot a hog in south texas that had a heck of a shield on him, they get thick and tough.I have been hunting hogs here in Texas since the early 90's and if the hog is in the 200+ range you might want to consider a quartering away shot (no matter which b/h you shoot). Or if he has a real big front end on him.....When you take a quartering away shot it will allow your arrow to go behind the sheild and into the boiler room...
I have heard nothing but good stuff about dos plumos too, I have a good friend that is taking his son up there for an exotic hunt this year....Good Luck and let us know how it turns out for you
Oh and by the way I have taken in the neighborhood of 75 hogs with a mechanical broadhead, a vortex 100g pro. If you have had good luck with your b/h's use them. I have never had problems with my b/h's in the last 10 years but also keep in mind all b/h's are not created equal. I know guys that have had problems with other brands but I have heard all good things about the rage as well.....Again good luck....