Fa looks like La when using second voice

I discussed this topic in the forum some time ago, it was worked on by various people, and finally I was encouraged to post it here.
1. This bug shows up when using the "7 shape Aiken" notehead style. All the notes are symmetrical except FA, so when you are adding the second voice to a score, and both voices are singing the same note (unison), then one stem goes up, and the other stem goes down. The two notes fit exactly one on top of the other. Except for FA.
2. Except for "FA". When FA is flipped, or mirrored, it does not fit over itself, AND SO, WHEN YOU HAVE TWO VOICES SINGING "FA" IN UNISON, IT BECOMES VERY CONFUSING FOR THE SINGERS, BECAUSE IT LOOKS LIKE A "LA". This is basically used for a capella singing. It is not acceptable to have a FA looking like a LA for copies given to a choir.
3, I have inserted 3 files below. One is an MSCZ file showing the result if you do not try to work around the issue. Notice how the Fa is exactly like a LA. One is an MSCZ file where I have tried to work around the issue in various ways, and failed. Note how parts of the note and/or stems are blank, or the note is doubled in an unacceptable, non-standard way. The third file, an image file, shows what a FA should look like when two voices sing it in unison .