I went from a GTX 970 to a GTX 1080 Ti, and good gawd that was something. I only paid like $430 for the thing too (got it brand-new from a dude on [H]). My 1080 Ti is still in use in my secondary desktop. It's an EVGA unit, like all my nVidia cards, except my current card, and my first nVidia card, a Guillemot Hercules GeForce 2 Pro.
I think a lot of people forget that the GTX 1080 Ti was just a Pascal Titan X that they dropped 1GB of vRAM from, increased the GPU and vRAM clockspeeds, and disabled some of the shader units. A $1200 prosumer graphics card became a $700 consumer gaming champion. I think personally it might be my favorite nVidia card of all time. One of my friends only moved on from the 1080 Ti last year when he got Indiana Jones and the Great Circle (without checking the system requirements) and discovered that he could not run the game cuz the 1080 Ti doesn't have ray-tracing-capable hardware.