Sun Ray vs Bone White

How close are they?

ΔE 15.5, loose: different enough that you should pick on purpose. Bone White is noticeably darker, warmer than Sun Ray.

Can I use Bone White instead of Sun Ray?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Bone White is noticeably darker, warmer than Sun Ray.

Can I use Sun Ray instead of Bone White?

The same difference applies the other way round: Sun Ray is noticeably lighter, cooler.

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.