I've used ProActiv and it worked wonders, for me at least. I would recommend that you use it.
Acutane is much more potent but the side affects are HELL. When I took Acutane, my lips became really dry and it started to peel like crazy. After awhile, my lips were so red that people thought I was wearing lipstick. My sister got a bald spot the size of a quarter when she used it.
For the record, Jessica Simpson is promoting Proactiv as if she had been a user and success story. It's completely fake. She got better using other solutions but these guys were willing to pay her the $$$. As convincing as the long infomercial with her face plastered all over it sounds, it's false.
I was a ProActiv user for years and had so-so luck with it. Not a complete cure for me, but the best I could get.
Save yourself money. Go to CVS or Walgreens and pick up a product called "Acne Free" ... it is basically a knock off of ProActiv and has the same active ingredients, but for half the price and no shipping & handling...
I made the switch to the Acne Free about 3 months ago and can't tell a difference..