I ordered three test prints in two different sizes: two Fine Art prints and one standard Matte print. I'd really recommend anyone setting up a shop to order a few samples first, just to see how your artwork looks in real life.
It highlighted a few issues with lost highlight detail in my images that I can now correct before anyone places a real order. On the other hand, it also gave me a lot more confidence in the print quality. The paper is lovely and thick, the colours look beautiful, and the packaging is excellent.
Definitely worth doing for peace of mind!