hello Erich.
i base this opinion, and it is most certainly just that, on my observations from collecting eterna for many years now. the company just didn't produce that many labeled chronometers. i can't help but think that it wasn't seriously thought of as a flagship of the sort that i think of when i ponder the word. there are marketing materials out there from eterna that claim they were "in the big three" of chronometer certifications during the golden age of teh 50s and 60s. one would have to assume this claim to also include their ebauche wing ETA.
if i were to compare eterna to omega, and i think the comparisons apt, i would say the models line up well, if not in far fewer numbers. for every 10 seamasters, you may have 1 kon tiki. i think the centenaire lines up well with the constellation. but again, one can find a nice constellation fairly quickly. it takes a little searching for a clean centenaire.
but again, these are all opinions. i welcome yours, if different!
in the meantime, have a chronometer!