Get on their mailing list so you can get a free swatch. I chose
http://www.spoonflower.com/fabric/253127. The blue was medium dull on my computer monitor but it is actually very bright. I haven't tested it yet for colorfastness but I will before I use it.
This would be great for people who want mini-motifs to be scaled small enough for stitched block letters. I have a lot of designs in mind but don't know how to execute them onto a computer program.