Colors I can't tolerate are black or bright Ferrari red. I do like some rich metallic red, though. The red prototype looks good.
The white prototype looks good too. White is clean, modern, futuristic. White is classy without being stodgy. White is cool under the summer sun, and it's highly visible without looking garish. White is logical. Unfortunately, it sometimes seems like half the cars on the road are white. If you're driving the fastest production car in the world, and it's the same color as half the cars on the road, that's kind of a downer.
Grays and silvers are photogenic, and they show off the car's form beautifully, but the monochrome is too blah. It disappears into the asphalt. I prefer something with some hue, some chroma, some tint. I like soft metallic colors, not soft enough to be called pastel, but not super-vivid Skittles Taste-The-Rainbow colors either — or McLaren colors, haha! Something halfway between Porsche stodgy silver and McLaren angry fruit salad, please.