Was looking at some pics, another way to put it is the flat white is a warmer, softer color, less harsh. The metallic is definately cooler with blue undertones as you mentioned. Personally I wouldn't be comfortable ordering Cararra without comparing side by side at the dealer. Here's a couple comparison shots. Cararra Metallic is the color on the Cayman GTS at the bottom. Standard white is the Boxster Spyder. Just by looking at pics I prefer the Standard, it looks more classic Porsche to me, but would need to see for myself in person if I was ordering now.