Review (5/5): Will not smudge, ever.  Truly.
I've been searching for a long time for a mascara that would actually be waterproof and not transfer to my undereye area - without success. Until now. I have to echo what everyone else is saying here: once applied, this stuff Does. Not. Budge. It curls, it thickens, but y'all better be prepared to have this stuff on until the apocalypse, because I still haven't managed to really clean off the first layer I put on four days ago. And there's not much time to second guess once applied because it dries within 2 seconds. I took a shower within 5 minutes of first using this product (for testing purposes) and gave my face a good wash, and... I honestly couldn't believe it. I almost cried with happiness. Even if I had it wouldn't have mattered, because this mascara apparently requires an army of nanobots to clean off. I'm in love. I've finally found The One.
So, the pros:
Yes, it lasts. Boy howdy does it last.
It does not smudge. It does not transfer. It becomes bound to your soul as well as your lashes.
Cons:
This mascara laughs in the face of typical eye makeup removers. I still haven't figured out how to remove this stuff (not that I'm really complaining) but another reviewer suggested oil cleansing with a microfiber cloth, so I'll give that a shot once I get tired of looking fabulous. (Seriously, it's almost like I'm wearing falsies.)
This product, because it dries so quickly and is of such an unusual consistency, does not take kindly to additional coats. (This is not a problem for me, as the first coat is more than impressive on its own.)
Again, due to quick drying, if you've got any clumps you have to act fast to comb them out. Just be careful with application (don't overload the brush) and this shouldn't be much of an issue.
Important note: Normally when applying mascara, you want to get deep into the root of your lashes. DON'T try that with this mascara. You might get little flecks or fibers in your eye and it is not fun. If you must, use another mascara to get at the base, and use this unholy formula on the rest.
I cannot recommend this highly enough. But just be sure you know what you're getting into. If you're big into having a totally makeup-free face before bed, be prepared to spend an extra few minutes each night forming a prayer circle and experimenting with ancient alchemy to get your lashes clean.