In spite of all the if's and but's and unknowns I have continued my "fade tests" through the summer and while not wishing to re-start the interesting arguments in previous posts I would like to share my results. The samples were measured today, having been exposed to the same conditions of light, temperature, humidity, ozone etc etc since April 4 2011. This is what has happened to the three pigment inks - Epson K3, Inkjetfly and Conecolor - all printed on Harman Gloss Baryta (as it's now called).
As before, each colour patch shows the original printed colour in the top left and the colour after exposure in the bottom right. The Epson and Inkjetfly are showing very similar fading but the Conecolor is visibly worse. This is especially true of the darkest colours where the "blacks" are fading to dark brown.
As I've said before, not a definitive test but it is a direct comparison. It looks to me as if the Inkjetfly is on a par with the Epson K3 on this paper and with this exposure.
Just for the record, I have submitted samples of the Inkjetfly/Harman Glos Baryta to Aardenberg Imaging but I am still waiting for them to go into test.
I am considering my options for non-OEM ink in my Epson 4800. I like what I read about the Cone inks being so compatible with the Epson inks but these tests do suggest that InkJet Fly might be a better choice in terms of longevity.