I know the vRS bumper is a bit lower at the front and a bit more straight down and in, whereas the older bumpers (like mine, although mine's a bit modded) have more curvy gradual lines in and under, which means the splitter does not work as well. I have no plans to fit one as I think it affects the aerodynamics at speed. I think my smoother bumper and curves makes it a little better.
The vRS bumper will go on any other fabia, but you would need to find the round foglights (mine are square) and make sure all the trim is there. I like that bumper, but I just want to keep mine more "old skool" looking - retain some of the car's original style.