Comment by antonholmquist

Thanks for your reply! I don't agree that concurrency is a mess with Core Data, it has good support for this. Of course you need to be careful to get things right, but this goes for whichever technology you are using. As for upgrading the app, if you are doing anything else than a lightweight migration you need to know what you are doing, but that problem doesn't at all go away if you roll your own database layer. I believe Core Data is actually of great help in solving those pretty complex problems.