This prevents creasing which for me is only an issue when I wear creme products on my lids, it also makes my shadows pop, so it basically does what a good primer should! It also stops my nyx jumbo eye pencil from smudging all over the place and creasing, which was a real problem for me!

I was incredibly disappointed with this product. After reading so many great reviews and hearing so much hype over it I caved and bought it about 2 months ago (therefore I've had a decent amount of time to test it).
UDPP has been my go-to primer for donkeys years and has never done me wrong however TFSI just couldn't take the heat when it comes to my oily eyelids.
After a measly 3 hours my smokey eye had been reduced to a single greasy brown line in my crease and my eyelids looked like I had painted a thin lair of oil onto them. Not a good look. I never have experienced this with UDPP, which has kept my past smokey eyes immaculate for hours on end.
I also felt that the consistency of TFSI was much too liquidy and set too quickly to allow for a decent adhesive surface for eyeshadows to stick to in comparison to UDPP which gives a somewhat 'tacky' finish as well as sufficiently concealing any veins/discoloration on the eyelids (which TFSI offers none of).
Overall I was very let down on this product and in the future would rather save my money and purchase UDPP which is only marginally more expensive but of immensely higher quality.

This is my holy grail of makeup products, I got it as a gift from a friend over two years ago, and I still have about half the tube left even though I use it everyday!
I have very oily shiny eyelids, and love putting bright pigmented colors on my eyelids, and this stuff really helps make sure it doesn't crease. At the end of a normal day, my eye shadow looks like I freshly applied it.
I have went to raves and been out in very hot weather while wearing this, and it gave me minor creasing but not enough that anyone would notice.
I recommended this to my mother who works a very busy hospital job, and she thanked me because it worked well for her too!
Usually I'm not that open about spending that much on makeup, and for how much it APPEARS to be (But the tube lasts longer than you would ever think!), but I would DEFINITELY buy this again!

This product does what it says it does without burning my sensitive eyes. I also like to use it on my brow line to keep eyebrow pencil on longer (without smudging off), especially in hot, humid weather.

This is a great primer. I have used it for at least a year, and have had no problems with it. The only negative I have to say is I kept it in a container in front of my window and it got rather soupy, but that was my fault. After I moved it away from the sun and used it for a few days it went back to its original consistency. The price I think is rather fair since it lasts so long and you pay for the quality. Two face does not test on animals and some of their products are paraben free. I would buy this product again.

This is my HG eye shadow primer for the following reasons:
1) a little goes a long way.
2) it goes on smooth and absorbs quickly (i found that the urban decay and lorac primers are a little too thick for me)
3) love that the product is a squeeze tube so you can get it all out (vs urban decay's original potion that you couldn't get the last drop out with the wand, but they've now caught onto a squeeze tube)
4) really does what it says. I haven't had any shadow or line smudging in my crease and it really brings out the shadow color vs when I don't use it

I've only tried a few eye shadow primers, I figured they did what they were supposed too, the kept my shadow from creasing and held my shadow on longer, then my friend made me a make up goodie bag for Christmas and this was in there. I started using it this summer and I didn't know what eye shadow primer was until this! I live in southern California, we've been in 110 degree heat and my smokey eye doesn't budge. I cleaned my house and was super hot so I jumped in my pool and swam a bit my mascara was gone and my face make up but my shadow a fairly heavy smokey eye was in place just slightly lighter, this stuff holds your shadow on like glue. It goes on silky smooth and leaves a nice base color, the eye shadow glides on smooth and it never creases on me. Love, love, love this primer.

I find this primer does not last a full day without creasing.

This primer is really good. I have oily lids and if I use any eyeshadow (even the good quality ones) they just crease and look awful! Before this I used the Mary Kay primer and I found that it was so hard to blend and it wouldn't hold up the eyeshadows for too long but THIS one is amazing! You don't even feel it in your skin and works wonders :) Eyeshadows keep in place, blend really well and the colors show stronger and prettier. I recommend this one even for people with very oily lids.
On a side note, the packaging is SO cute! I love the baby blue tube!

It's my first eye primer and I really love it. I'm looking forward to try more Too Faced products, I thing they are amazing!