I recently purchased a Platinum Century 3776, F nib. Even for a Japanese pen, I found the F nib to be closer to an XF Japanese nib. Great pen. However, I think a M nib on this pen would be more to my liking. I especially like the color I purchased and was thinking, if I bought a second 3776 (different color, of course), can I swap the nibs between the two pens?