Redbubble is great at returns if anything is not to your satisfaction.
Art of Where does not take returns, but if something is not right, Amy will take care of it for you. The quality of fabric is excellent, but they run small. I would suggest at least one or two sizes larger.
Pixels is a branch of Fine Art America. There are all sorts of cool things to order from yoga mats to t-shirts which are all of excellent quality. The art prints from Pixels are exceptionally well done. If you would like Amy to help you mat and frame one for a reasonable price, please contact her directly at 303-656-1428 or firstname.lastname@example.org.
Excellent quality and easy returns. They put things on sale often.
Before you order, scroll down to learn more about each printing company, and some of the quirks they have. Amy has some pieces by each manufacturer at Mastiff Studios to ensure quality. She believes you will be pleased with any item you order. Redbubble and Pixels take returns with no questions asked. Art of Where does not. If you are unsatified with their products contact Amy directly.