Managing security in a VCF 5.x environment is complex, but the 6V0-21.25 material made it clear. I particularly benefited from the practice on vDefend (NSX) distributed firewalls and gateway security policies. The technical depth regarding threat prevention and IDS/IPS configuration was exactly what I encountered in the exam.
 

Coming from a security architecture angle, I liked how the 6V0-21.25 exam material highlighted segmentation and workload protection decisions common in VCF environments. It encouraged slow, thoughtful reading. Reviewing NSX notes in parallel helped fit the pieces together.