I have tried and discarded about 4 or 5 primers for face or eye area. Smashbox is great. Unlike primer for painting a house, primer should not be thick, opaque and heavy. Smashbox is thin, light, and clear. So it does not feel oppressive on the skin, and the foundation or powder I put over it has a clean, smooth base. That's the right idea.
The eye primer has a dispenser for smoothing directly on contact under eyes. I prefer to dab tiny dots and pat with my fingers for more control of where it's going. The slight pinkish tint is not seen when blended, and probably is to counteract dark circles.
This is a good eye base for older women as it's so thin in texture it does not weigh down the small wrinkles or bags. It it not total coverage, but it also won't crease or give that pasty look by glopping as time goes by.
Very happy with Smashbox as primers go, a light touch is the key, and in my limited experience this is superior to other similar products.