Crazy Egg shows you what visitors do on your store — heatmaps, scroll maps, click maps, session recordings. StoreVitals shows you what's broken on your store — security issues, broken links, missing alt text, slow pages. Different problems, different tools.
These two tools answer different questions. Crazy Egg answers 'what are users doing?' StoreVitals answers 'what's wrong with the site?' A high-converting store usually needs both — Crazy Egg to optimize the funnel and StoreVitals to monitor the foundations underneath. Crazy Egg can't tell you your security headers are missing or that 12 product images failed to load. StoreVitals can't tell you the checkout button is below the fold on mobile. Use them together.