I got a pano roof too on my late 2004 x5, reading all the posts just how common is it?1 in 10, 1 in a 1000 or just pure luck depending on whether or not the drain holes get blocked?yup would be good to know if they can be cleaned out now and again?and where exactly the drain holes are on the sunroof cassette?anyone know what the best routine maintenance is?and how do they clog up, i cant see how leaves can clog up the channels unless you keep the sunroof open and close it without realising it is full of foreign objects.....any advice would be great on this,ta