Hi Phil,
The guy rang from colorific to see if ink had arrived and that it was ok, as it wasn’t in the machine at the time I tested it with a swab dipped in the ink and painted it to the vinyl, so not exactly the same as printing with it, it seems ok but printing may give different results. Something I did notice about a year a go was that the yellow changed colour. I have clear cartridges as it is a bulk ink set up and when filling the yellow from a new bottle you could see the old ink was bright yellow the stuff was more a golden yellow, makes no difference on the prints but in the tank you could see the change in colour so the yellow ink has certainly changed a little.