Frontier models can effectively review individual merge requests for vulnerabilities. However, using them as the primary scanner for an entire enterprise codebase proves costly and unpredictable. Deterministic scanners like SAST offer predictable costs and consistent findings for every commit. AI-based reviews, on the other hand, excel at catching intent-based and novel flaws by utilizing contextual information. SAST provides reproducible audit evidence essential for compliance. AI scans can generate exploit tests, reducing false positives and building developer trust. The future of security involves integrating both SAST for baseline coverage and AI for deeper reasoning. AI cannot fully replace SAST due to its probabilistic nature and cost at scale. Reproducible audit evidence is crucial for frameworks like SOC 2 and PCI DSS. AI-based reviews can identify business logic flaws that pattern-based scanners miss. Security teams should leverage both SAST for continuous scanning and AI for complex reasoning checks.