Gogoprint (Singapore) Pte. Ltd. gogoprint sg Refused to reprint or refund for their own mistake, instead wants us to pay more to resolve the mistake that they made

Very disappointed in the solution that gogoprint gave for the printing of letterheads. We printed the first batch in small quantity as trial because gogoprint said they do not accept actual letterhead to match the printing, only pdf file.

The first production was not good. We did not complain because perhaps our pdf file is the problem.

Second batch, we corrected our pdf file and we accepted the quality. We thought the quality of this batch will be reflected in the next bulk purchase.

Third batch, we adjusted a little bit more for the pdf file to make sure the color and some area are better than 2nd batch, and we print in bulk in expectation it will at least be near to the second batch if not better.

But the third batch is 'DIFFERENT' from the 2nd batch, quality not accepted.
We explained to gogoprint the problem. The answer, the different is in printing small and big quantity. Small quantity using digital printing, big quantity using offset printing, so that's the price difference. But this is not mentioned in the website or quote.
The color difference is not only 10%. it's alot. They still do not want to see the actual printing that show the difference.

They offered a 30% discount for the next purchase. but I will be stuck with 2000 unacceptable letterheads already.
Also how can we trust that the next printing will be the same, when we cannot make sure the small quantity is the reflection of big quantity and they do not even accept the actual printing difference? how can we make sure the pdf can be reflected as it is in the printing?

We are very disappointed and will not print with gogoprint again.