There is so much potential with all 3 of the engines; UnrealEngine4, Cryengine, Unity3DPro, just UE4 really drove the nail on the head flush with the board, unity drove the nail in but it was loose, and cryengine drove it in halfway and bent.
I was using those three engines at the same time about year ago, UE4 Beta, Cryengine, and Unity3DPro doing some prototyping for a few game ideas i have and all were great but UE4 Beta blew them all out of the water by the pricing and what they have to offer, AND it was in a beta phase! The time in which i could develop something for Cryengine or Unity3DPro i could do twice or even thrice the amount of work in UE4. I didn’t like the fact Unity3DPro was primarily a scripting platform and programming Cryengine was really hard to get any help with, although once i found some help and figured stuff out it seemed everything just kept getting weirder. it really boiled down to what i was paying for and what I was getting. With cryengine, you get allot and pay a little but also you get little help. Unity3DPro it seems you pay allot and get a little and then keep paying for extra stuff that should have been included with the original version and still have to maintain it yourself essentially, with ue4 you pay a little, get allot and you get allot of help, even from the devs. All in all, the quick time in which i could get stuff running in ue4 and have it look fairly decent, i was just getting other things barely setup in Cryengine and Unity3DPro. The visual scripting element was a huge deciding factor as well, but really i don’t even use it much, only for prototyping stuff, then program it based off of those blueprints; I love that. I was also familiar with the UDK class hierarchy already and i felt it was the right choice for the kinds of games i wanted to make plus the UE4 templates and free marketplace stuff. It’s just a win win win for me.