Of all of the Parker-style gel ink refills, this is head and shoulders above the
rest. It lays down a smooth, consistent line with no skipping, and it's a nice
blue color. I like this .5 tip, and think it's a good thickness, but if you want
a bolder line, they also make a .7.
If you want a gel refill for your Parker-style pen, skip the others and get
this. The rest are skippy, globby junk.