Certifications if: 
- You want faster, focused, practical skills 
- You’re targeting specific roles/tools (e.g. ML engineer, data scientist) 
- You’re already working and need flexibility 

Master’s if: 
- You aim for research, academic, or leadership roles 
- You want structured, in-depth theory + application 
- You can commit time and cost 

Brief take: 
For staying relevant and deepening applied + theoretical AI skills, certs are great short-term, but a Master’s is a strong long-term investment if aligned with your career goals.