I can understand your attraction to these speakers. Big, bold cabinets. Lots of drivers ready to get the air (and music) moving about the room. As a speaker geek (I own a speaker patent) my guess is that the speakers were just a bit on the picky side in placement, but once dialed in, all the stars lined up and highly rewarding (and emotionally engaging) musical experience ensued. The fact you hung on to them as long as you did is a validation of their design. Your current choice of speakers indicates you have "good ears", so the Koss’s must have gotten a lot of things right.
Selling the speakers outright will certainly get them in the hands of someone with "skin in the game" who will have a high appreciation for the speakers. I also see the value of giving them to an audio club, and in the hands of someone who’s finances are a "couple of db down" from purchasing quality gear on their own.
At any rate, I hope your "old friends" find a good home. They deserve it.