I use both Quilters Showcase and Keepsake Cotton when they are on sale. I make prayer quilts and many of them go to people in nursing homes. Most will not last 5 years as the families often don't want them when the person dies. So I'm happy to use "inferior" fabrics if it allows me to brighten the life of someone for a few months or years. Would I like to use quilt shop quality fabric? Sure. But I have a choice of making one quilt of expensive fabric or three of less expensive.
I also like Marshals Dry Goods fabrics. I often buy a bolt for $1.85 a yard, which ends up around $2.25 with shipping. Their quality is excellent.