I am not a fan of any of the LashBlast mascaras. They just don't do much for me. I've tried the original (meh), and the LashBlast Fusion formula (double meh), but I had to try a mascara that claimed to last 24 hours. Had to.
That said, it lasted all day without flaking or smudging. Did I get "a blast of lush, volumized lashes," as Cover Girl claims? No. I got slightly volumized lashes, with a touch of extra length. Oh, and a bit of aggravation when it came time to remove this stuff. I've been using Clinique's Take of the Day Balm, and 24 Hour lasts through that, plus normal face washing. I have to use an eye makeup remover, then the balm, and then wash my face. That's a lot of steps. I don't really like to spend that much time and energy on my lashes, because I really don't want to pull them out during the process of getting them clean.
If you need a mascara that lasts forever, 24 Hour is for you. If you want a mascara that lasts all day and is easily removed, however, don't bother with this one.