For web scraping purposes ScraperJS and ScraperJS would probably use the same lines of code, however ScraperJS has most of the tools you need for web scraping, something that CasperJS lacks (that's not their main goal). ScraperJS is move flexible than just CasperJS. If you want static content just use the static scraper and get lightening fast results. TL;DR: CasperJS is great but it's not made for web scraping.