Anyone trieed this with MB?
My understanding is that you get free nib exchange but only within a certain period after buying the pen (no idea if they check for sales slips or anything). I did this with a 149 some years ago with no problem.
I have a pen that is a few years old but only dipped and wanted to see if I could swap out a M for a F nib. If not, I believe their section prices are pretty rude, no?
In which case I guess it is off to the nibgrinders....