Hi, sana09! My personal preference between the two is the NARS Body Illuminator because it is not oily like the NARS Body Glow. I don't like the feeling of greasiness and the Body Glow made me feel oily whereas the Body Illuminator is not greasy at all once it has dried (after about 5 to 10 minutes). I also like the color of the Body Illuminator much better and I think that it would be a much prettier color on your olive skin tone than the Body Glow.
Hope this helps!
Hmm. The body glow is an oil and has a beautiful smell, moisturizing, with shimmers. The body illuminator is a pigmented with highlight reflectors, also has that same beautiful smelling oil in it, only available for Summer, .... I would choose the body illuminator because I think it would be easier to apply and less oily. But if you had hoped to wear it year round as a moisturizer then the body glow....