RAL 7028 Dunkelgelb (Initial) vs UK Light Stone

How close are they?

ΔE 7.8, close: similar, with a visible difference side by side. UK Light Stone is a little lighter than RAL 7028 Dunkelgelb (Initial).

Can I use UK Light Stone instead of RAL 7028 Dunkelgelb (Initial)?

Usually, if you are not matching paint already on the model. Close match (ΔE 8). UK Light Stone is a little lighter than RAL 7028 Dunkelgelb (Initial).

Can I use RAL 7028 Dunkelgelb (Initial) instead of UK Light Stone?

The same difference applies the other way round: RAL 7028 Dunkelgelb (Initial) is a little darker.

ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.