"Blood" did vary considerably. When new it was crimson, not quite maroon but soon started to fade to an orange hue. Precision/Phoenix paints do make new and faded colours for blood and the faded looks more like most of the photos around.
The custard was more yellow shade than not but again faded to a pale cream. Precision/Phoenix custard is a more yellow shade and I have toned it down a little when painting models.
I did have a photo of a Britannia with about 5 different shades of blood and custard coaches behind but cannot find it at the moment.
You will always get someone thinking a colour is wrong as apart from new/faded, sunny/dull etc our eyes all see shades different to others.