I worked on three of them! While there are some serious issues with Frostbite and everyone loves blaming it for everything, its role in sabotaging huge projects is definitely overblown.

There are some issues with workflow and it is true that the UI definitely was, as many at EA said, "by programmers for programmers". But it's a very capable engine in the right hands.

That said, I'd pick Unreal any day for a AAA project and Unity or Unreal for smaller projects.