Uni-ball Signo Broad UM-153 Gel Ink Pen - Blue Ink

Honestly this is a really, really fabulous pen for whiting out areas in need of correction. I've tested at least three other gel pens against it and in order of similarity, some either held up well or just did not match the opacity and flow of this pen.

http://www.jetpens.com/Sakura-Gelly-Roll-Regular-Gel-Ink-Pen-0.4-mm-White/pd /531 Held up marvelously in terms of opacity and flow and to be so cheap I was really surprised by how well it worked in compare to the Uni-ball. The Uni-ball is fantastic if you have to spot correct a semi largish area but the broadness of the pen tip makes it harder if you do very fine spots so the 0.4mm of the Sakura is a good twin to the 0.8mm of the Uni-ball.

http://www.jetpens.com/Pentel-Hybrid-Gel-Grip-Gel-Ink-Pen-0.8-mm-White/pd/50 0 this one was just not as great as I had imagined it would be. For the cost which is close to the Uni-ball Signo Broad, I really did expect for this pen to be just as opaque but the ink was actually rather thin over the pens and I tested this against a variety of inks. It just did not do as well as the Uni-ball and Sakura.

http://www.jetpens.com/Pentel-Sunburst-Metallic-Gel-Ink-Pen-0.7-mm-Silver/pd /1309 Using the silver as a kind of aid for anyone considering on buying the Pentel Sunburst Gel Ink Pen in White should JetPens ever bring it in stock. Still medium tip and much like the Hybrid, it was just not as thick as it could have been. Repeated layering doesn't seem to be a huge problem but I like being able to put down a coat of white from the onset.

In summation, if you draw, stick with the Sakura or the Uni-ball. Pentel is a great pen company but they just need to thick up their white or make it more opaque.

This link shows my test and the pens I tested these four against.

http://fc01.deviantart.net/fs71/f/2011/364/7/c/white_ink_tests_by_colanah-d4kqd qu.png

I am a cancer screening lab tech who uses these pens to mark abnormal cells on glass microscope slides. My profession has been looking for a white pen that writes well on glass and fits under the objective lens of the microscope for thirty years. Finally! A pen that does the job. These are great! They mark precisely where we want and flow well. The lines show up nicely on the background of the black microscope stage. Don't ever stop making these or I'll have to retire...

For some reason white is a hard color for most gel pens to get right, but Uniball is the best I've tried (and I've tried a LOT). It's smooth and bold, and doesn't have have the "I'm acting like I'm dry even though it's clear I'm full of ink" issue a lot of gel pens seem to have. If you're looking for an excellent white pen, this is it!!

I loved this pen! it didn't skip and its great for touch up on drawings and manga!
*recomend this to any manga drawers*

I'm kind of disappointed with these because I can't use them for what I really wanted them for, and I bought 2 :\

The white that comes out is a thick white, but the width of the line that the pen makes is too thick for the kind of detailing I wanted to do.
Also, there is a peak/ball wherever you lift up the pen. For the most part it settles down. It's not a huge deal, especially if you're just using them for writing, but you see the little dot at the end of a line... I'm a little picky because I'm using them for artwork.

It just depends how picky you are if this would matter to you or not ^_^;

If I had bought these in a retail store, I probably would end up returning at least one of them to get something else, since I think it will take awhile to use up just one for what else I can find to use them for on artwork.
I wanted them for a fast and more convenient way of making line details, but they can at least be used for a quicker way of doing dot detailing ( quicker than my dip pen and white ink )

So, that is just my opinion based on what I was looking to use them for.
It's not a very expensive item, so if you're looking for a nice thick white ink, I'd recommend trying one ( but only if you're already buying over $25.00 worth of items to get the free shipping :)