The Uni-Ball Signo UM-100 does not equal the Uni-Ball Signo UM-151 (aka the DX). Why is that? I'm not sure, but the two pens write nowhere near the same. While I had no issues at all with the 0.7mm UM-100 - in fact, I think it is great - I am having a really tough time with this pen.
The tip of this pen is scratchier than I am used to from a Uni-Ball product, causing the line to be uneven and inconsistent. For me to use an 0.5mm gel ink pen regularly, I need it to have a very clean line, and this one doesn't. I have no issue with the 0.7mm version, and the 0.5mm DX pens that I have are awesome, so what is going on here? It could just be a dud, and since this is the only 0.5mm UM-100 that I have, I will order another one to see if I have the same difficulty with it.
I'll give this one a pass for now based on track record, but I will update once I get a new one ordered.
Click here for the XL review.