Re: Factory Data Reset & Marshmallow
I won't be, unless there are issues, but usually I do not.
THIS...
I'll always give this advice:
Hope for the best, plan for the worst.
Major upgrades have a lot of moving parts, one of which is often the runtime libraries that really run all of Android. When those change, you really run the risk of having some bits on your app cache and data that aren't exactly happy to play in the new sandbox.... and your once well-oiled-machine running phone starts to cough and spit. When that occurs, a FDR usually clears that right quick. But not everyone has such issues.
Still, make preparations... make sure your photos are backed up, go check your backup settings and make sure stuff like your WIFI config, contacts, etc... all are backed up. Plug your phone into a computer and make a backup of your internal storage, etc.... That way if you DO have to do a reset, it's as painless as you can make it.