Is Vitaran Skin Booster really good for skin repair?

Lately, my skin feels very tight from within and I can feel the overall texture has become rough, so I am considering Vitaran.

I am interested because it is said to moisturize and firm the skin's foundation, but I am curious to know how long it took for those who have actually received it to notice changes.

Usually, on what day after receiving the treatment did the internal dryness subside and a moist glow start to appear on the surface of the skin?

Also, I would like to know when you felt a significant difference in the skin texture felt on your fingertips or the firmer density when washing your face.

I would appreciate it if those who have personally used Vitaran could share their honest experiences or the effects on skin texture improvement. Any advice would be a great help.