I chose Rejuran because it was the cheapest in the area. It was a 4cc hand injection. I don't think Rejuran is a procedure that depends on the doctor's skills. However, I liked the doctor because he was very thorough and kind. Even though it was winter, I felt like my insides were slightly dry. About a month? Doesn't last long. I've been to expensive dermatologists, but I really liked this place because the managers and staff were friendly and the waiting time wasn't long. However, if you have sensitive skin, you should consider all injection procedures. Even after receiving skin botox, I suffered from small pimples. This time it was a little less, but I still got some pimples. I don't know if Rejuran itself is very good, but since it dries out a lot in the winter, it doesn't seem bad to get it once as a preventive measure.