The main difference between the two is one is a car color and the other is a color in a J-Crew catalogue. I think I'll get a silver car. Wow that sweater looks great in Opal. Similar to the difference between charcoal and dark grey, heather and tan, green and spring meadow, etc. So if you want knit rims then definately go opal preferably in kashmir wool, (keeps those tires nice and warm in the winter) but if you want to be less stylish and more functional go silver. Hope that helps.