I tried pencil eye liner back in high school when I was just learning to do my eye liner. For those who are beginners, I would say pencil is easier to apply. A great pencil eye liner should be waterproof to avoid smudging. Urban decay glide-on eye liner pencil is amazing!
However, I like very precised eye liner, not too thick which usually happens with pencil. So for years I used liquid eye liner. MAGIC INK JET BLACK LIQUID EYE LINER is perfect! I swear it's so black, to be specific, it's jet black! Doesn't move, doesn't smudge, black forever, the eye liner is so precise, easy to apply because of the length of the brush. $20 that will last you forever. You can find it at Sephora, Macy's, Bloomingdales, others.
HOWEVER.... Gel liner is now my favorite of ALL!!!! I have used a couple, and I have to say the brand doesn't matter much because when it's gel it sticks to the skin much easier and glides on so smooth and easy. I do have to say it's a bit harder to apply compared to the pencil or liquid. So, if you are not very used to applying eye liner, this is not the best choice for you. However, every girl in the world should own a gel liner and practice, practice practice. I have used MAC MAC Fluidline gel eye liner , Inglot Inglot gel liner #77 black and others. The prices depend on the company. But if you don't want to spend $15-$20 on a gel liner, if you reside in New York they have these Beauty Supply stores that have very inexpensive makeup and hair products. beauty supply store locator. Their gel eye liner can be up to $3 and guess what? It's just as good :)
I hope this was helpful to you !!! :)