On the thought of whether to continue with Chamonix or choose another color, I did a little research and found these comments in various trade publications.
"Titanium dioxide, also known as titania, is the most stable of all known white pigments."
And
Color v. White Pigments
A good white paint typically has greater resistance to abrasion and marking than deep tints and accent colors do, because the clear bases used for deep colors lack the titanium dioxide (TiO2) that makes white paint white.
But TiO2 is not just a whitener. It’s harder than most color pigments. That hardness makes a big difference in the paint’s resistance to impact and marking. So a paint film loaded with TiO2 will be more robust than one loaded with soft color pigments.
I had a white '93 Volvo 940 wagon in Hawaii for 10 years. After I added 100k miles to it, it had 225K miles and the paint still looked very good. It was left outside and given no special treatment. I saw many newer cars with base/clear coats suffering clear coat failure. I pulled a fender off of a newer car with half the miles because mine was dented - perfect match.
Your mileage may vary but I'm sticking with Chamonix.
Ian