My skin is extremely oily?

I'm 17 and to keep it short, my skin has always been problematic. As an early teenager my skin was dry, but when I was 14 I developed some severe acne (its genetic as my dad had it). Because of this I went on medication for my acne and now its cleared up and I only get the occasional pimple. Since my acne has improved my skin has been very combination, so I have dry areas and oily areas. Because of this I've always had problems with foundation as it sticks to dry spots on my face but my skin gets oily in about an hour.

Now my skin is as oily as ever, and I feel like I've tried everything. I look after my skin really well, I wash and cleanse it twice a day, I exfoliate 3 times a week, I wear a light amount of makeup. I have also tried numerous primers and setting sprays and they still don't stop the oil coming through after an hour. I blot and powder during the day but this makes my makeup go really cakey. It's just disgusting as it looks like a have a thin layer of water on my face.

Also, I think the excess oil has made me develop these little sweat pimples on my forehead. They aren't whiteheads, just small pimples. They aren't noticeable but they are still a pain.

What's annoying is that I have friends who don't look after their skin that well and yet their makeup looks flawless all day and they don't have to touch up at all.

I'm about to give up and invest over a hundred pounds into buying a Clarisonic Mia as I hear these work like magic. What advice would you give? How can I prevent the oil? Will the Clarisonic Mia help control this oil? Is it just hormones and will the oil stop eventually?

Thanks,

L

xxx