Silver because the color lasts and does not fade as much as solid colors. I have a 2003 titanium silver X5 and the paint still looks really good. I've seen many black x5s that look old and worn out and white x5s that look 'stained' and old. So in terms of resale value, silver wins hands down. Black won't hide scratches or blemishes and white will will look dull and 'stained' over time.

 

Moreover, silver has that mirror appearance that reflects colors from surrounding in a very cool way.

 

funny thing is both diamond and irdium cars were sold before i was able to purchase.

ended up with palladium silver, like the color changes between differnt light as otakki was mentioning

 

we need pics

 

Though not as intense of a color change as iridium silver, the palladium silver still has that property and is a nice color to have.