I had the same "problem"

Is like this:
- I like black, but black "shrinks" the car (visual)
- I dont like Silver grey. I have my wife's car (Renault Megane sedan) and it's looking good only when is just washed. The rest of the time is seems to be dirty with only few traces of dust.
- I choosed titaniul silver (+ grey leather). This color seems for me very good and the car doesn't seems to be very small (comared to X5)
- I like Magic Blue, but most of X5 & 3 here are like this..

Gray



vs

Silver