Sansa Clip Zip without format.

Hello everyone, yesterday i got my new Sansa Clip Zip, and i install rockbox on it without any format. There is possible to have problems without make a format, or i not must make it?

And btw, how long is time to fully charge clipzip with usb cable?

It is not necessary to format the player before installing Rockbox.

Using a computer, it normally takes 3 hours or so to completely charge from a fully depleted state.