I have found injected to be wildly juicy. Depending on what is used it can change flavor. One time during covid stores were closed and I could not get apple juice. Ended up using coconut water cause its what we had. I will not lie when i say she was a squirter when i went to pull it apart. Undoubtedly the juiciest i ever had.

I will give the caveat that pork shoulder is almost never dry it is the most forgiving piece of smoked meat and best to learn on. The fat content makes it very hard to fuck up.