Review (4/5): Noticeable difference...
Love this product! I've been using it daily for about 3 weeks now and there is a noticeable difference in the firmness of my skin. I don't see any change as far as wrinkles but I only have fine lines anyway so that wasn't an issue.
I initially used alone and one pump is not enough to cover my face so I blended it with my daily moisturizer (Olay total Effects) as instructed on the label and it worked perfectly. The one thing the Olay doesn't do well (even though it's supposed to) is even out my skin tone and plump up the skin - adding the Collagen Booster Serum fixed that.
There is no odor and it absorbs well. I highly recommend this product and will probably check out if they have something to replace the Olay moisturizer.