White - This was my least favorite of the pens. As much as I freaking love how bright it is, but the formula was a little too thick and it dried out on me. Now this totally could have been an error on my part, I may not have put the cap on properly. But when the tip dried up and I was trying to use it, it started to leak out of the casing. Not cute. I also am basically out of it, which was an error on my part because the first time I used it I pressed the tip too long and I wasted a lot of product. So learn from my mistakes and remember to make sure the cap is on properly and don't press the tip down for more than a couple of seconds!
Pearl White - I liked this pen, this was my third favorite. The formula, although a little runny, was really easy to apply and the color is really pretty. I wouldn't call it "white" but more of an off-white, like for an American manicure. It is a bit silvery in some lights as well, it has a lovely frosty quality to it.
Pearl Pink - I think that this one was my favorite! I didn't think that I was going to like this color that much but I really did! The formula was perfect and I like how it was easy to see it filling the tip so that I knew when to stop feeding polish to the tip, I wish that the tips of the white ones weren't white because it is much easier to see with a different color. This is probably the hardest one to match colors to, but it goes great with cream colors and pinks!
Black - This one totally comes in as my second favorite. I love the concept of a black tip. The formula in this one is perfect as well, it is very opaque in one coat! Again having it be a different color from the tip really helped a lot. The only problem that I have with this one is that if you don't put on a good topcoat, it will chip quickly, and it is very noticable if you are wearing a light color under it. Otherwise I love it!
So I hope that this is a better review for you all and more through about each individual color as I experienced it!
* I was sent the White and Pearl White pens by Nailene. However I bought the Pearl Pink and Black with my own hard-earned money, that is now much I like these pens in general!