I've tried many and this is by far the best. Goes on smoothly, no clumping, no crumbling and really elongates my lashes. Removes easily with make up remover and does not irritate my eyes as it doesn't have those nasty little fibers that can fall into your eyes.
I'll never buy diorshow iconic mascara without the primer again! This stuff is incredible! My mascara tube will last much longer because I only have to do one coat of it when using this primer.