So far (knocking on wood) I have not had problems with any bleeding or uneven shrinkage when washing finished quilts made from non pre washed fabric. The only reason I ever even started not washing was due to precuts. So I haven't been pre washing but I've noticed recently that I sneeze a LOT when using unwashed fabric, and get itchy hands. So for sure anything that doesn't get washed later (purses, small bags, other household projects) get made with pre washed fabric. For quilts I probably won't but if I keep having these allergy issues I'll have to wash it all. I dread it.