This is the other thing with HxD and I think it's very important for a hex editor, it handles huge amounts of data in the correct way. HxD can open entire block devices, or per-process/whole system RAM, and it all works without bogging down.

I've tried a lot of lesser hex editors that get cooked the moment you try to open a 4GB file. I don't know if the field I'm in skews this, but most of the time if I'm looking at a file in a hex editor, it's relatively large and I need to find a tiny amount of information in it.