I love the bright colours that many Europas were painted. An added bonus, they are visible.
I seem to remember many years ago - I think it might have been when I was in high school - which means it was an age ago! - that Mercedes did a study of what color is the most visible under all weather and light conditions and I thought the results were that white was the most visible. Obviously, that wouldn't hold true during snow!
That was certainly a long time ago and I could easily be wrong (as readers here surely know!) but I don't think it's a question that bright colors like yellow, orange and lime green would also be VERY visible colors and red under most conditions.
Incidentally, I've always had a thing for white cars and my first Europa was white so I had to go with white almost regardless of how easily it could be seen.