Great news, Seansbrew, and congrats again. Your group's response certainly is a reputable confirmation of things you had already observed. I met Mr. Joe Zon yesterday at his shop. They got the Zon hardshell cases in stock, so I picked up in person what I ordered awhile ago for my Sonus 5 when still living in SoCal. He confirmed the instrument I bought as a second owner was indeed a specialized order completed in March 2002. 3-band equalizer toggle switch confirmed. The nicest guy in the world, and very accommodating, as I was running 15 minutes late, on a Friday afternoon, given I got temporarily lost. Perhaps kind of like meeting Clapton or someone.

I'm kicking myself hard for not bringing a camera, or getting his autograph on myt string set. (dumb oversight on my part). Can't believe I'm only 10 miles from his headquarters.
Edit: I've had TI Flatwounds on my Sonus 5, but picked up his 40-125 ultrasonic string set, custom light guage, especially well-suited for Zon fretless, according to their website, and won't likely look back for a very long while to come. I'm swapping them in tonight. but would like to know more of your own string observations in coming months.