This calamagrostis (feather reed grass) was new this spring, so it's a little thin, but I am loving it beside my patch of bergenia. In fact, any ornamental grass would pair well with bergenia, thanks to their contrasting height and texture.
I also like to specifically place ornamental grasses where they will be back lit for part of the day i.e. not up against a building or fence. This one is viewed from the kitchen window and I know I will be even happier I planted it in when I am looking at it in the middle of winter and it will still look great.