My last white attempt was to apply a light "white+blue" wash over the entire yamato plastic. Even if it was great for artificial lights, it was not for sun light. So I clean the bluish wash and I applied the red on the cap to test, and I was happy with the red accent.
Since then, I bought Tamiya X2 White acrylic to test, but it wasn't better than the Tamiya white fine primer. As suggested to me, I think the best option is to completely cover the VF-1 with a white primer to have all the different parts in the same white.
We should ask @chyll2 about its custom VF-1X++ ?