I also own a 2000 540i. So my expectations of the 2010 550i were pretty high. It had to be the same or better. My expectations have been met. It's carbon black with cream interior includes all the M sport trims you can get. It's an excellent vehicle and fun to drive. If my wife asks me to get milk and eggs, I'll do it 2 trips. The vehicle with it's 19" wheels rides on rails, a notable growl can be expected from the mufflers after 4000rpm. Surprisingly smooth suspension. Has many hidden features not all described in the brochure. As with my older one, it's 10 years ahead of its time.
The side adjustments to your back, thigh adjustment, heated seats that allow you to control the blend from behind to back, heated steering wheel, ski bag, definitely the i-drive, parking distance sensors front and back, electric retractable mirrors, electric rear blind, comfort access, new car smell :)
Unlike the 2000 540i, it does not have an engine temperature gauge. Not even on the i-drive vehicle info/status. No full size spare. CODE function to lock out vehicle is no longer available. Little $3 Allen wrench to open/close sunroof manually in case of emergency is sold separately.