Anyone using mass gainer here?

I've ordered my Serious Mass this week whilst getting a gym membership soon, but a couple question still lingers especially as an underweight women with inconsistent diet and busy lifestyle, so I'm wondering if any of you ladies with experience of taking one can share some thoughts:

- Should one take the shakes daily? I would only go to the gym 3x per week

- Do you still have to eat in calorie surplus/minimum on the days you are drinking it? Or could you eat in less amount since the shake do contain 1k calories

- How long until you see visible results in weight gain? Heard it took about a minimum of 2 weeks for visible changes

- Any acne or hormonal changes etc after taking/stopping them?