As soon as you have more than one developer you should move to source control. Just being able to merge commits from two different developers cleanly will make it worth it.
It’s a bit of a learning bump but my god it’s good. And I have to say, being able to diff inside UE made my life much easier last night.
If you want to be a much more effective developer, source control is the way to go. And git is definitely the source control you want to use now that there’s some UE support.