Firstly, I have to disagree with the claim that it leaves the skin matte, it doesn't. As every setting spray, it helps blending all the makeup products nicely together, it takes away the powdery look if we use powder products and leaves a beautiful, naturally luminous look to the skin which I absolutely love and I think that's the main advantage of using this spray.
I've noticed that it does help slightly with the oil control, minimising the need of blotting/powdering the face throughout the day but it doesn't stop the natural skin oils come through makeup. If you thought this product would be the answer to your prayers for stopping your skin from being very oily, it's not. You'll still get shiny but probably a bit less than normal. I also used the spray before applying my foundation and then on top of my finished makeup and I think this way I got the best results in terms of oil control.
While using this spray my makeup definitely lasts longer looking good. My foundation normally quickly disappears from my nose and chin but using the spray the wear time of my foundation in those areas was extended for an hour or so depending what foundation I used.