Originally Posted by
pisquee
I doubt the refill carts are the problem, although what's in them may be.
If they're unbranded then you don't know what ink you actually have - it may be the best ink in the world, or absolute garbage!
One thing you will need to get your colours right is an ICC profile - if your supplier can't provide one, then you will need a custom one making - without it your computer doesn't know what to do with the inks in your printer to mix them into the right colours. Even the best/most expensive ink in the world is useless without an ICC profile.
As for the mugs fading in their print at the top/bottom of the mug - this can be due to the mugs themselves not being straight enough and/or your press not being tight enough (although probably a combination of the two.)