I've used the Print Space for a few months now, and the quality has never disappointed. They have been the only company I've found so far that print what I see on my screen, rather than a saturated, blown out version. I use very subtle pastel tones in a lot of my work, and they produce them perfectly. Tip - download their Photoshop print settings for the best results. Also, it's worth buying the sample pack of print paper for reference - it's really useful if you want to maximize the quality of the end result.
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