The only people who would have hardware issues are people with ancient machines, which wouldn't be able to render them at all. Any potential FPS drop would be <1 so you wouldn't notice it.

I still can't see too many people being pleased about having so much drive space eaten for the sake of a vanity image, plus the jump from 512 -> 1024 won't be noticeable for the majority of people. (you'll need to be running the game at a stupidly high resolution)