My Cub is the plane I fly the most and I fly it off a grass runway with no problem. You just have to learn how to ground handle a Cub. Landings are a breeze, its the take offs that are a challenge. Once you get it to go straight down the runway, it's the first 25 feet or so after lift off that the real the fun begins. You can never be too sure how it's going to react. You have to be on your toes.
Have fun
Jeff