After reading a post by Ashlyn, I purchased a pen from Fountain Pen Revolution.
Here are a couple before-after images.
The “K” was drawn with a Pelikan 14k Medium nib
The “L” was drawn with the FPR Steel Ultra Flex.
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This “L” doesn’t take advantage of the power of the flexy-flex, but the The nib pops when I’m doodling hard, as I did below.
(The top two alphabets are the flex nib, the third one is the Pelikan Medium nib.)
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Understandably, the steel isn’t silky smooth like the gold nib, but it’s a great value at $30 (half for the body and half for the nib). Plus I’m willing to push a $15 nib to the limit, while I doubt I would have the courage to do that with one that costs 10x).
Time to start practicing if I want to wield its power and breath life into my lines.