 I have had several BMW's from the M3C to the X5M.The 550ix with sport line package satisfies my need for a nice looking, powerful 4-dr sedan that is less challenging to drive than an M series. There are two fatal flaws for me.1. Windshield area and angle makes it impossible to get out of too much direct sun.Even with cooling seats and the a/c running, it can be quite uncomfortable in summer.2.After 5,000 miles, still getting only 14 mpg.Have had problems with variable comfort settings (comfort, normal, sport and sport plus) and battery not holding a charge.The battery issue came up with X5M as well.Ridiculous placement of what is supposed to be an ashtray. 