I was using compandsave.com. About $6 per cartridge. We were getting good results with the films, but have since switched to film positive ink (different printer) and the films are a bit darker.
All said and done though, the Dmax with their ink was 3.05 which is good enough for the tiniest of the dots. Two of the award winning shirts we did were done with that ink, so it delivers what's needed.
pierre