I used to brine, and had good results. Then I started injecting which made the task easier and less clean up. I used Chris Lilly's Injection but found it to be salty to my tastes, I cut back to almost half the amount of salt and it is still good. last year I switched to OakRidge Game Changer Brine as my Injection and have nothing less than great results with it.
I now, always use OakRidge Game Changer Brine as an injection. I Use fruit juice (Peach, Pear, Apple, or White Grape) for added flavors. For every 8 ounces of juice add 1 Tablespoon of OakRidge Game Changer Brine and then inject into the pork. I inject right through the cyro-packaging to save with cleanup, using different angles through the same hole to prevent leaking. I used to rub and let the pork sit overnight, but now I'll rub a few hours before smoking depending upon my time constraints.
When cooking injected pork butts I find the bone begins to wiggle at about 187°, I pull and rest the pork in a cambro/cooler for 3 to 4 hours, and pull the pork just before serving. I find the OakRidge Game Changer Brine keeps the pork exceptionally tender, moist, flavorful, and it pulls in very long strands which is great for sandwiches.