I just purchased this mascara and was previously using MAC False Lashes Extreme Black. I like False Lashes but am a sucker for trying something new. I don't generally like waterproof mascara, but decided to give this one a try after asking the SA at MAC if the waterproof mascara would eliminate the mascara smudging off under my lower lashes half way through the day and she said yes. Today is the second day I've worn it and did notice (compared to False Lashes) that I had to use a mascara comb after applying the mascara to the lashes, which is no big deal just something new for me to do. It has not yet smudged under my eye (at least the past two days it hasn't). The only downfall and I know it's because it's waterproof, you really need to have makeup remover to remove the mascara. Again, no big deal as I currently use makeup remover anyway. So far I'm liking this mascara and if it continues to remain 'smudge free', it just might be my new mascara!