I have always had a problem with mascara smudging and/or flaking during the day, even with waterproof mascara. So, I fell in love with this sample. For the first time I could put mascara on in the morning and it would still be on my lashes and not underneath my eyes at the end of the day. And, I should note that it also looked good - no clumps, lengthened and curled my lashes, etc. - the whole shabang. I bought the full size product as soon as my sample ran out. I hate to say it, but I liked the sample size more. For some reason the full size product clumps like crazy, so I have to wipe the wand off with a baby wipe before each use to remove some of the excess product to avoid clumpy lashes that get stuck together and won't seperate. However, the tubing technology still works, so I will continue to put up with the goopiness of the full-size product. At the end of the day (literally), if I can wear a mascara all day and night and feel confident that I won't have smudges and flakes under my eyes, I'm sold.