Agreeing with everyone, yes both of the files are useful and in some instances as mentioned above, one file is more useful than other.

But at the end of the day, both files are there for a reason. My personal opinion, I rather have both files on hand. If you need a quick overview of a project, do you really want to read through an entire file? While there are other instances in which you must have every possible detail of a project to make a final decision on continuation or budgets. Its not a personal opinion in this case as the question implies, we can come up with situations where one is better than the other. Its a matter of using the file to make the best decisions for your workplace and project. This or the other file is irrelevant, what matters is how you use those files in your job.