Why would savegames and everything else be deleted if you're going cfw 3.55 - ofw 3.55 - ofw 3.70?
Are you saying back everything up as a precaution or it's always deleted?
From my experience saves, game data, trophies, etc never get deleted with just a firmware upgrade.
Edit: oh you're saying format...eff that..I don't really think it's necessary..
Just delete all homebrew, use a file manager to get rid of backups on hd, use a few different wipe programs and I think you'd be fine.
Sony is wanting people to upgrade and I doubt they go outta their way to mess with people who decided to switch back.
I suppose if you wanna be 100 percent sure you can be safe then go ahead but you can't back up trophies so no matter what those will be gone...
IMO it isn't worth it.
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