As far as I can see it has not much in common with casperjs, apart from the fact that it can use phantomjs.
CasperJS can also scrape dynamic websites. What criteria would someone want to use ScraperJS instead of CasperJS for that task? Are there features in ScraperJS that don't exist in CasperJS? Does it take 10x less lines-of-code to accomplish the same task? Etc.