Definitely try it out for a week or maybe even a month before you get a big supply.
I am very oily/acne prone. I went to Sephora and they made me up a sample. I instantly LOVED it, my skin felt so great. I ordered a bigger bottle. Before it arrived I broke out all over my chin/neck, worse than I ever have since I was a teenager. It was pretty under control before I tried Purity, I just needed something new as what I was using became discontinued/hard to find.
I mean, it was so bad I didn't even want to leave the house. I really wanted to love this, and I did for a very short time. It just goes to show that everyone is different! I actually wound up clearing it up with Neutrogena's acne line, but it took months to go away. I hope you have good luck with it!