Thanks for the replies guys. For some reason my Asus won't write working copies of SafeDisc games. When I wrote the image with my old Toshiba DVD burner, it worked just fine.
So I think that, currently, the combination of a Plextor Premium (can burn SecuROM 4/5) and a Toshiba/LiteOn DVD writer (for everything else) would be the perfect 2-drive combination. Do you agree?