I really like this product. It does not dry completely like for instance the MAC one, it remains tacky, but not sticky.
Whatever mascara you apply over top really adheres and builds onto the primer. The effect is quite dramatic which is kind of the point.
You are able to achieve volume as well as length. It also lasts pretty well throughout the day and the best thing is that your lashes don't feel crispy - they can still bend without causing breakage.