This pearly, non-mattifying primer is super-lightweight. I only have a sample (right now) so I've been trying to make it last by only using it sometimes. And I notice that people go out of their way to compliment my skin when I wear itthat never happens when I don't. (I use Maybelline BB Cream as a foundation over the primer, because I like a light, natural look.)
For a long time I used Smashbox primer, in the neutral and the green (red-correcting) formulas. Until I got this little Nars sample I didn't realize how deadening the Smashbox product is. Nars' "radiance enhancing" or "light optimizing" version keeps my skin looking hydrated and glowy without being obvious, glittery, or weird. I have sensitive skin and haven't had any problemsbut neither do I wear it every day; in any event, I moisturize day and night with Aveeno Clear Complexion moisturizer, to combat my skin's tendency to react to skin products. My skin stays clear as long as I stick to what I know won't break it out.
This primer is expensive, but makes my Nars SG stay on so much longer and just looks smoother. There is a shimmer like others have mentioned but it disappears.
I use this over a moisturizer because I have dry skin. I have stopped using powder unless I'm getting photos taken, so I needed a primer to make foundation stay on better, since I skip powder. This does that. My sculpting powder, blush, and overall face just looks ultra smooth using this.
I got this sample from one of my perks. It was okay. I like how you only needed a little bit and it worked really well as far as my makeup staying put. But my HG is the Smashbox Luminizing Primer. If you just need a simple primer with SPF 15 then I say go with this one.