Others have reported that keeping data unticked should be fine, so I went ahead with that route, but others have reported the opposite. With no root I can't use Titanium Backup, so if there are backup alternatives that doesn't require root, I'm all ears.
I'm attempting to downgrade down to 4.2 or 4.1 from 4.3 to root my 5502 while keeping my data. However, every 4.1 or 4.2 ftf I've tried results in a boot loop at the Xperia wave animation. I didn't have any issues going from .101 to .569 and vice versa, only down to .310, or .67.