There are vector images and bitmap images...
Vector images can be scaled to any size without distortion as they merely comprise of lines and fills...psd despite it's layers does not produce a vector format. Adobe Illustrator does...which can be converted to EPS files and PDF files...pretty sure their printer can sorter it though as Illustrator has an impressive trace tool...
If these are just being printed then it won't be a problem...
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I do prefer B Rabbits however and think it's a wasted opportunity not to take it further...