I have been using Kona "Snow" for my Dresden plate quilt. The color (as suggested by the board) is perfect and the fabric feels nice. I have been a bit surprised at how many loose threads I get along the cut edges. I had thought higher quality fabric would not do that as much. There were no strange colored fibers in the weave that I have found and I have certainly found them in the past with other brands.
The rest of the quilt quilt is 1930's reproductions from several name brands. Moda, RJR, etc. Some are certainly thicker than others. Again, I expected more consistency with the higher end fabrics.
This is my first quilt made with what would be considered all LQS fabrics. I have to say I think I will continue to buy whatever fabrics appeal to me and feel nice whether they be Wal-mart, Joanns, or LQS. I just have not seen a quality difference to make up for the price difference.