The new King Charles III, is signing all sorts of documents these days and recently had some trouble with a fountain pen. It may have been an official or a borrowed pen but in any case on this occasion it oozed ink and he complained this happens "every stinking time!"
I love writing with my pen. I'm left-handed and over time the nib has adapted to the way I write. Fountain pens are personal to the user. The ink in mine flows brilliantly but might not if loaned to another, say right-handed user.
Ink residues are inevitable when filling and I keep a well-blotted napkin to wipe the barrel and remove excess.
Love the ritual of filling the pen - every inking time!