Car paints for Standard Surface and OpenPBR are vastly different presets. Why?

[ssjenforcer191191191]

I decided to try the standard surface again after updating my Arnold version.

I made a car paint material and made it white.  However, it looked quite greyish in the IPR.
I did the same thing with an OpenPBR material, and it looked white like it should.

I realized that the preset for Standard Surface gives base weight 0.5 instead of the OpenPBR.
Which one is 'accurate'?  I don't see why they should be so vastly different.  It obviously looks white only if I use base weight of 1.0.

The same goes for the two tone paint, which offers a 0.8 to 1.0 comparison.

Why is the preset so obscure for Standard Surface?

[lee_griggs · Accepted solution]

They are there just as a guide. If you want a realistic car paint material, then use the Car Paint shader.

[ssjenforcer191191191]

I see.  Thanks.

I had forgotten after getting so used to inserting nodes.

Even with a 0.8 base weight, the car paint shader material still retains the white colour look.