I want to install the UII to connect to and develop plugins in my organization. However, I can't decide between installing it using the package manager console (as discussed in some nice blog) or using the download site from Microsoft.
Both feel right...
The answer is that both are correct sources for the current UII DLLs.
The choice of which to use is a question of your development methods.
There are pros and cons to each but Stackoverflow is not the appropriate place to debate opinions per the rules.