G Suite offers built-in, machine-learning-powered spam filtering, quarantine features, and Data Loss Prevention (DLP). It's generally easier to set up and manage for basic security needs. Proofpoint, as a specialized email gateway, provides advanced threat protection (ATP), including URL defense, attachment sandboxing, Targeted Attack Protection (TAP), and email encryption. It integrates with G Suite for a layered approach, offering more comprehensive protection against sophisticated threats like phishing and malware. Proofpoint also provides features like phishing simulations and security awareness training. Experts recommend layering Proofpoint on top of G Suite for organizations needing robust security beyond G Suite's basic features. G Suite and Proofpoint can integrate using APIs to allow Proofpoint to enhance G-Suite's default functionality.