I have yet to hear a single success story from organizations that implemented SAFe. I've heard of, and experienced first hand, plenty of organizations that abandon it in less than a year. SAFe is the methodology that managers and C-level people want, precisely because it provides all of the additional roles and reporting. It also presents itself as something for teams to use, without higher levels having to adopt Agile.

In my experience, ANY Agile implementation will fail, falter, or produce too much drag if the organization doesn't adopt from the TOP down. You cannot retain traditional management structures in an Agile environment because it cuts the teams off at their knees. Agile isn't something you do, it's something you are, and if the entire organization doesn't engage, you're Agile in name only. I've also heard this described as "TACO Scrum" - Teams And Ceremonies Only. This frustrates development teams and leads to churn because the methodology makes no sense in an environment where there is no trust.