I use Unity, mainly because that's what I started with and I haven't thought of a good reason to switch just yet. I work on 2D and 3D projects and it can handle both. I tried Unreal a bit, but didn't get far. It's very interesting with a lot of features for sure, but I did like being able to use C# in Unity and continuing to develop that so that I could use some of the knowledge on non-game projects also.