dunderhi, looks like you correctly interpreted BMWs incentive rules. Do ED on the 650 and get BMWCCA and load up USAA and BMW app incentive on X5. Congrats on the new cars but I still think you should go with the Mercedes GL. Mercedes also has a USAA discount program.
2008 Mercedes-Benz CLS550 Iridium Silver/Black Leather -- P2/321/881 (leasetraded 1/10)
2002 BMW 325i --Topaz Blue/Natural Brown Leather --SP/PP/HK/CWP/Bi-xenon (Sold 9/06)