Every time I cook a butt, I inject. I generally don't follow a specific recipe, except I use Apple juice, and blend up until a powder a couple tablespoons of my rub. I often put a some Franks Hot Wing Sauce into the blend.
I'm doing a butt for Superbowl, and I am trying a whole new injection, no apple juice, but I'm not going to share until I taste the out come.
1)Use a strainer and dump 1 packet of Lipton soup mix into it. Discard the noodles and keep the soup "rub"
2) 1/4 cup Karo Corn Syrup
3) 1 tablespoon of prok rub
4) Top this off with 2 cups of White Grape Juice
In the comps we use a product called FAB (as do most of the big guys) instead of FAB. The soup mix has similar compounds like FAB but is much cheaper. These compounds help seal in the injection. Otherwise it ust cooks out.
Remember - pork like sweet. I would never inject pork with Teriaki - beef maybe but not pork.