Note too that permanent ink suggests a strict set of maintenance rules; the
ink can all but permanently damage the pen if you forget to rinse it on a regular
basis. You'll need to flush the nib section and feed regularly when you use permanent
ink; otherwise the ink will dry to a hard non-water soluble material and stick
to the mechanisms, permanently.
We like Pelican ink. Still, we recommend
going to www.inksampler.com, where you
will find a detailed analysis of a range of inks.