It is worth noting that...
It is worth noting that this refill uses standard semi-solid BALLPOINT ink (not
a gel or hybrid type.)
I used to buy Uni Jetstream SXR-80-10 refills and just cut them to size to fit
my mini-pen, until Uni came out with the SXR-200-07 D1 sized refill. It's great,
but you'll go through its hybrid ink extremely fast. I decided to try out
various ballpoint ink refills. I've tried: Cross, Dupont, Lamy, Schmidt, and
more. Monteverde was the surprising winner, consistently giving the smoothest
feel and the most consistent line with the least skips.
There's no doubt that D1 refills with gel ink (like Zebra JSB and ESB) or hybrid
ink like (Platinum or Uni) give the smoothest experience with a darker more
consistent line - and of these my personal preference is Uni (with Zebra a very
close second) - HOWEVER you will go through ink like it's going out of style.
Among D1 refills using a true semi-solid (standard ballpoint) ink, Monteverde is
head and shoulders above the rest in my book.