It is a good plan to use iTunes to back up before doing any updates, and then do the download and install. It is also best to encrypt these backups so it will include passwords and other secure information. I backed up all three iOS devices ahead of time in prep for the update, but did the install over my home WiFi. No known issues. As with all updates some have issues, some not.
Tom Wilds
Blythewood, SC
2016 Newmar Baystar Sport 3004
2015 Jeep Wrangler 2dr HT