Any birth control pill with more than 30 mg of estrogen is prescribed to help with acne, so you should be ok if that is the case with estrostep. You can be prepared for an initial breakout, if you are prone to breakouts already, with any new pill, so whether you take this one or another one, you will still get a little bit of a breakout. Stick with it, though...after about 2-3 months, you will likely see a big difference.
By the way, Yasmin isn't all it's cracked up to be. I got horrible cystic acne while on Yasmin and as soon as I got off of it, I cleared up. Now, I have no cysts at all after month 4.