I am in my mid-30s. Is 300 shots of Ulthera enough, or do I need 400 shots?

I decided to get Ultherapy because my facial contours have started to sag overall and jowls around my mouth are becoming slightly visible. I'm conflicted because after consultations, some places say 300 shots are sufficient, while others say over 400 shots are needed for a noticeable lifting effect. I'm also afraid to blindly increase the number of shots because I'm worried about losing too much weight in my cheeks. How did people around my age usually handle the number of shots?