Is the PMP Certification sufficient ?

"Is the PMP Certification sufficient to be a successful PM ?"
"Is the PMP Certification sufficient to get a job as a PM?"

These questions are like asking

"Is the course completion certificate from Alliance française, good enough to survive in France ?"

Alliance française, provides a structured method to learn French. It is up to the individual to learn the language and develop the ability to speak them. Better you utilize the same, better you will be your time in France.

So is the whole exercise of getting PMP certified. This provides an excellent opportunity to
1. Learn the broad framework of project management as suggested by the Project Management Body of Knowledge
2. Unlearn some of the wrong approaches that you might have been using in your role as a Project Manager
3. Develop a deep understanding of the concepts and the learning objectives in each of the project management areas

Hope this answers the question!