Red is the color I carry most often, and that's not counting my Rouge Vif makeup clutch that I carry EVERY DAY inside that day's bag. Red goes with just about everything, and is a real attention-grabbing color. I think the sight of red makes people happy. It's an instant de-drabber.
I just saw the vermillion IRL tonight at NM. It's fabulous. True red like others have described, unlike rouge vif that has black undertones. It's fabulous