I know it says don't post here if you are not going, but I have just retuned from Spa (second time there). What an awesome place. You DO NOT need Movits for Spa. My quattro gmbh brakes were easily good enough. There is only one really hard braking point and that is the esses after eau rouge. The only other one is the busstop but it has changed now. You now curve right before the chicane so its not a good idea to stand on the brakes anyway. Remember the cooling down lap is 4km long. Easily enough time to cool off.
Tim's CSL has no chance against an RS4 at Spa. Trust me I know and mine is unchipped. Even a GT3 can't get away. I have to confess the Enzo was untouchable though
You are going to have the time of your lives. Nurburgring will be a huge anticlimax. Great experience to have been there but nothing compared to Spa.