I've both bought AcneFree in stores and ordered on the website, and I highly prefer the website. After a couple orders I've started receiving random free product! I don't believe it was a mistake because it's happened twice (retinoid X2, second time also included a small sunscreen). I was elated, because I am very, very broke but need AcneFree because acne is a medical condition, and it also helps my mild psoriasis. The retinoid goes fast, so that's especially awesome! I'm sure it's a free sample type deal, like Sephora has, but it was totally unexpected and even though I'm not expecting it every time, I'm very grateful!
If you've had good luck with Proactiv I would definitely suggest trying Acne Free out. They system is very similar at a fraction of the price.
Answer: I'm not sure about studies but they do seem to work. My daughter has had very good results from these products.
Answer: My daughter has used this off and on for years and it usually takes about a week for her start seeing her skin getting clearer.
Answer: They sell full kits and I would suggest picking the one that best suited for your skin. They offer the standard oil-free system, a maxiumum strenght and sensitive version.