If your primary focus is strictly on Technical SEO Auditing, SEMrush takes the win here. Its Site Audit tool is incredibly intuitive, groups issues clearly by severity (Errors, Warnings, Notices), and gives you actionable steps on how to fix JavaScript rendering, broken links, or canonical issues. It also tracks your audit health score over time very cleanly. Ahrefs is decent for technical crawls, but their core strength is heavily tilted toward backlink analysis and keyword research rather than deep on-page diagnostic reporting.