Yes, do give it a try. Lamy tests their pens with their own blue ink, so if it doesn't work you know something is wrong.
I'm not a huge fan of their blue ink myself, but I have a blue cartridge in a brand new Pacific Al-Star. The pen out of the box was giving me problems with ink starvation when used with the converter, so I switched to a blue cartridge and now it is working fine.
A thorough flush with Pen Flush solution helped cure my pen's problems, it might do the same for you too. A couple manufacturers offer this product, here's some choices:
I use the Goulet brand. You can also mix up your own; google for some how-to videos.
Edited by ErrantSmudge, 09 November 2017 - 17:23.