Easy mod with big results. If you have a Volvo with a choppy window, 9 out of 10, it will be the window sliders. They are quite easy to replace though. Tip: buy them on Aliexpress for cheap!
Decided to mod the intake flap to a more direct version, which should aid in forcing air into the airbox. Performance could be better, although right now I dont have the means to measure this.
When I bought the S80, it was evident that the plastic trim had seen better days. So I decided to spend some time and repaint it black. As expected, it transformed the car tremendously. I highly recommend this!