The amount of time it takes for you to upload your files depends on two factors:
1. How much data you want to upload, and
2. Your connection speed.
Click here for a tool that allows you to approximate your upload and download speed. Choose from the listed options a city that is as far as possible from where you are (i.e. if you are on the East Coast, choose a West Coast city and vice versa). This will give you a worst case scenario approximation for both download and upload speeds.