The Israeli Air Force roundel decal is the wrong shade of blue compared to both real life and all israeli planes ingame.
As you can see in these ingame examples the roundel decal on the right (how the decal should not look) is a dark purple and the one that is already on the plane on the left (how the decal should look) is a subtle bright blue
here are pictures to showcase how the roundel looks like in real life
and lastly how it looks in the customization menu
(if the topic catagory or anything else is wrong please do tell)