JavaScript Charts API: Flot jQuery Plugin OR Google Visualization?

I am looking for a charts library to be displayed on a website. I will use intensively this library (for area, line and bar charts mainly), so I prefer to secure my choice before starting implementing.

Using jQuery and Google Visualization API

I am using Google Visualization API and jQuery. When I include both scripts as well as my js script ( report.js ) in the head, the page show nothing, even if report.js is empty. But if I remove the last line, it is ok.