Heavier is the way to go. Here's a few reasons.
1. Just as a rule of thumb, fast light bullets are a no-no in heavy brush. They can and probably will deflect, mushroom half-way to the animal, and generally suck.
2. In heavy brush, your game should be fairly close when you see it, thus the extra FPS aren't a necessity.
3.From What I've heard of hunting hogs they have thick skin, strong muscles, and big bones. You want a big bullet that will give you the best penetration.
4. Wounded hogs, aren't fun hogs. You want A bullet that will break brush all the way there, and proceed to tear through skin, meat, and heavy bones an on into the broiler room until the bacon is very dead.
Hope you have fun, and please, go with the 230 grain.