So yeah. A decent amount of versatility (see the video) and some luvverly explosions. But it does kill people, and not just "evil" people (for lack of a better word) since it's been used in wars that aren't particularly just... but there's misuse of this stuff in every war. So I've got to forgive it a bit. It is pretty dang cool.
Final Score: 9/10
As for the lethality, I believe I touched on that already. It'll blow off limbs, it fires fast, and it causes nice little explosions. Not the biggest explosions though, and obviously if you're incompetent with it then it won't be very useful. But it'll blow holes in most things, and stop a lot of things in their tracks. Definitely effective.
I wouldn't recommend trying to procure one, as I really don't think domestic use would be a very good idea. I mean, imagine trying to fight off an intruder with a grenade launcher... Well, I guess it would work pretty well to scare them off so long as you don't shoot. But you don't want to destroy your stuff. I think it's best if you defensive gun-loving types stick to your shotguns and whiskey.
And that was topic number two. Wow. But yeah. Same spiel. Comment, follow, blah blah blah. Just keep reading and let me know what you think.