The 550i is amazing. It handles beautifully. The power is so amazing. It just pulls you into the seat. The headlights are awesome. The sound system is A+. There is nothing that I could think of that needs to be changed in the 550i. The seats are also a huge deal. They are super comfortable. The only thing is it eats fuel but the highway fuel economy is really good. But it's worth paying extra for fuel because the power is a great feeling.