If you have a program that run through the stitch pattern like Wilcom Truesizer or any digitizing package and you know what kind of support stitches etc. the design requires you know if it is good. I give a digitizer a few chances to get it right; as I do not know when in their career the design was digitized, and experience is the best teacher.
Sometimes the file will come up as invalid or corrupt, or when it opens it isn't in one peice you know spread out across screen, or they just don't stitch out properly.. these thing occasionally happen so you need to weed out those designs..Hope this helps...Marian