I'd happily use a '7 for dispatching a pig. I think that the knife is pretty much ideal for a pig hunter. The handle design makes it safe. I really appreciate not having a guard on my Beckers. A guard can make a knife more problematic to hold in a sheath, and guards can get in the way on a working knife.
I was once asked, on the spur of the moment, to help a guy retrieve his monofilament fishing net in some fairly unpleasant weather. I was not dressed as I would normally be for working on a boat. I had leather hiking boots on, and I had a homemade hunting knife with a short brass guard.
The boat was a runabout maybe sixteen feet long with an outboard motor. The net was set near a lee shore maybe a mile away. The boat owner was wearing one-piece overalls. Neither of us was wearing a lifejacket (as has been our lifetime habit... although not necessarily a good one. We carry lifejackets in the boat as required by law).
The net was set fairly close to a rocky shore, and the sea was quite choppy. Instead of approaching the net from one end, the skipper took the boat alongside the net on the windward side. Within a few moments the propellor got caught in the net and became surrounded by a tight binding of strong nylon netting. Duh.
We couldn't pull the net off the propellor and we were being washed toward the rocky shore. When we reached shallower water the owner jumped over the side and attempted to hold the boat off the rocks. The boat was hit by a wave and got pushed over the owner. I jumped in with my boots on. I asked the owner for his knife (everyone carries a decent knife on their boat, right?).... but no, he didn't have one. I only had my fairly short hunting knife with the protruding guard.
If I need to slice cordage in a hurry, I would choose a sharp knife with a fairly long, thin blade. With a long blade you can use a decent sawing motion.
I attacked the nylon with my knife. Nylon monofilament can catch up and tangle on anything, so as you can imagine the guard on my knife was not a good thing to have as the net swirled around in the water. I should add here that when working up close with monofilament nets, the buttons on your clothing are also likely to get caught.
Anyway... I finally cut off the compacted net. The net was wrecked and, as far as I recall, there were no fish in it. Fortunately the shear pin through the propellor was still intact and we were able to take the boat back to where we were staying.
Shortly afterward I gave the owner a nice stainless knife with a longish blade (and no guard) to keep on his boat.
I've stuck pigs using knives with no guard and just a plain handle. I like to hold the handle so that the base of it is jammed at least partially against my palm. I don't hammer the knife into the pig (which could result in my hand slipping down the knife), I hold it against the pig and push it in a controlled manner as best I can in the circumstances. Although it is sometimes safer to stick the knife in behind a front leg where you may encounter a rib, the preferred method that I've seen is to tip the pig over and push the knife in alongside the brisket. Sometimes I have pushed the knife handle into the pig as well to get a bit more penetration, and a guard would make this more difficult to do. When sticking a pig in the artery alongside the brisket, the knife doesn't have to go far in to be fatal. I just like to reach further for a quicker result if possible.
I am yet to stick a big pig with a BK9. I have pushed the '9 into a goat as described in another post, and I've stuck a pig with my BK2... although it didn't slide in as easily as other knives that I've used (even though the knife took considerable force to push in, my hand did not slip on the factory scales. I think the factory scales are fine). I've since made the point a bit sharper on my '2.... although I am unlikely to take the '2 on a pig hunt now that I can use a '9.
So yeah.... I think the BK7 is a great knife for the job. Best wishes from NZ.