I'm wondering what is the best method to upgrade WordPress, is it the "One Click" method or "Manual" update. I've used both methods, part of my process is to first test upgrades on my local machine after taking backups.
One Click method should be fine unless you're getting an error or you know you have some sort of customization in place that would require you to manually update in order not to overwrite certain files, or something. I think you'd know if you need to do it manually. Just backup your database and files first if you're uncertain.