Fat grafting to face in Korea - how long do results really last?

I have noticed volume loss in my cheeks and temples as I have gotten older (I am 45). I am considering fat grafting to restore youthful fullness. I understand that Korean surgeons are very skilled at facial fat grafting and achieving natural results. However, I have read mixed information about how long fat grafting lasts - some say it is permanent, others say much of it gets absorbed. Can anyone share their experience with facial fat grafting in Korea? How much of the initial volume did you retain? Did you need touch-up procedures? How does it compare to filler in terms of results and value?