I don't have an ACNE problem BUT my sister does and everytime we would go out to the club or somewhere like that she would always wind up using mine because it literally hid her ACNE so well!
I use Clinique Super-Balanced cover-up! It's a bit spendy but it lasts a long time. I always had a bottle for about 4-6 months and I use make-up everyday even if I am only checking the mail!
Seriously though, my sister loved it and it hides blemishes and red blotchiness VERY well!!
Good luck babe!