What GPUs do you use for game development with UE4?

I wouldn’t invest $1000 in a video card by AMD, yet.
I am running 1080GTX series now and I have no reason, that i can think of, to move back to a Quadro. Now, with that said, I would do any and all 3D work with a Quadro, you would be stupid not to. This is why all CAD machines have them (or should). They far outweigh the “gaming” cards of equal stats. Gaming cards are built for speed, dev cards are built for raw power. Like the difference between a 1970s GTO and a 2010 Honda Civic with all the mods.

For unreal, gaming card. For all your modeling and high-end 3D dev work? Quadro (or equiv). I wouldnt put AMD/ATI’s first born in my machine and expect magic to happen. Truth is, we dont know how it will perform. It might blow CUDA out of the water, it might not. I am the kinda’ guy that is very “go with what you know”.

Question for you is: Why arn’t you using a 1080GTX if its proven to work effectively for development ?
EDIT: ^ not you WhiteSky, “you” is a general term here