I've had this recommended to me, and I finally bit the bullet and bought a tube. Fortunately it was on sale at a drugstore, so I paid $2 and change. For that price it's pretty good.
What I like:
When I use this I do get really spidery lashes. They're definitely noticeable. I'll apply and then hold a Q-tip or my finger against my lashes to "set" the curl (also, I misplaced my lash curler). Holding the damp lashes up for a moment adds a bit of curl and hikes them up a bit so they're more noticeable. Once they set my lashes are definitely amplified.
I also like that the formula doesn't have any major smell. No fragrance that lingers after applying, etc. In fact, I can't pick up any scent, which is ideal because I personally loathe perfumed mascaras.
The formula is buildable. Apply a bit, wait, and go again. Two coats and my lashes are noticeable. A couple more coats and it's trashy good.
The price. I think this tops out at about $6, and there are often sales so you can get it for $3 or less. With drugstores having good return policies, it's worth a try.
What I don't like:
The brush, for starters. It's a fat curvy brush that comes in an hourglass shape so it's narrow in the middle. It seems kind of unnecessary, but in general I prefer a skinny brush instead of a big fat one. The bigger the brush, the more likely mascara ends up on my eyelids.
I also am not wild about the fact that this can apply clumpy. With some care it can be avoided, but it can easily look bonkers on lashes. (Good if you seek huge spidery lashes, but bad if you want more definition.) Best approach is to wipe the brush on a tissue before applying and build it up.
It can get a bit crumbly. Nothing major, but taking a peek now and then to make sure it's not migrating might be a good approach early on, to make sure it behaves like it should. I don't notice any major issues, but on watery-eyes or allergy days it never hurts to check.
Would I buy it again? Sure. With a coupon or when it's on sale I would say yes. Not for $6, though. And that's mainly because I can wait it out for a deal. Since it's suggested mascara should be pitched after three or six months, I see no reason to pay full price for it. At least not until I come across that grail of mascaras.