These LEDs are a very pale yellow, in comparison to the Golden Whites' pale amber. While the Golden Whites mimic the pale amber color of the incandescent bulbs of old diesels, these are a very pale yellow - hence the name Sunny White.

While you probably don't really want to mimic the sun with a headlight on your loco, the difference between the two shades, when lit, isn't that much if you're not looking at them side by side. However, the big difference is when they're turned off. While the lens of the Golden White LED has a deep amber color when turned off, the Sunny Whites are clear - looking more like the lens of an incandescent bulb. If the LED can't be seen, such as lighting through a light pipe, you'll probably want the Golden White. But if the LED is mounted such that it can be seen, you may want to opt for the Sunny White instead.