I'm in the process of setting up a new iOS 11 device, and got the Quick Start prompt at the beginning.
I've always used the iTunes backup/restore route as (as far as I know) it's the fastest way to do the transfer, keeping the passwords etc in the new device...
But I want to know if the "Quick Start" method requires an iCloud backup, or it might work off an iTunes backup.
Checking the apple pages Transfer content from your previous iOS device to your new iPhone, iPad, or iPod touch - Apple Support, the relevant section says:
Your new device offers the choice of restoring apps, data,tand settings from your most recent iCloud backup, or updating your current device's backup and then restoring
So I'm not too clear if it's just for iCloud backup or the
updating your current device's backup might also cover iTunes