The only ink sets I have are the carbon and selenium now, and I have pretty much settled on carbon only now and haven't done much work with it on glossy paper. I did a lot of testing with Platine and the K6 Selenium ink set about a year ago, but I recall hearing somewhat recently from Jon that the inkjet receptive coating Canson uses has changed so the measurements I have might not be the same as the current batches of paper. I might be able to make a few test prints with the K6 Carbon on Platine and then graph and post them later this week.
One thing that I have found when making QTR profiles for different K6 inks sets is that the color will change depending on how much overlap there is with the other inks (of course the QTR curves don't have the same shape as the Piezography curves, but still overlap with 3 or 4 inks at any given point, with the long tail built into the front of the curve rather than the end)
Richard Boutwell