I purchased this mascara about two months ago from Rite Aid and Target and I have been using it ever since. I have to say, it's definitely one of my favorites among all mascaras I've tried and the best mascara I've tried for lengthening.
I have been using both the waterproof and regular formula to see if I could notice a difference. The waterproof mascara is definitely a drier formula but they both work well at lengthening the lashes. I didn't notice any flaking and as for the waterproof claim, I don't wear mascara under water but both formulas have not run down my face or anything like that. Between the two, there really isn't much of a difference except for the fact that one is a bit drier. They both are very black and I find that both hold a curl for about the same amount of time.