I looked at phoenix yellow when I was choosing the colour for my respray and was only put off by the cost.
JRM told me that they done a mitsubishi EVO in yellow and to get it really bright and vibrant it needed close to 10 coats of paint, and before that needed to be sprayed white. The cost for labour alone was way way more than pretty much any other colour.
To make matters worse the EVO got keyed not long after it was done and needed a full respray again.
Personally I think a phoenix yellow needs a few black areas to tone it down a bit. I've seen one with a black bonnet, spoiler and wheels on Google and it looks immense.