I love southernbelle muslin, but can't find it around here anymore. I have to look farther north. At Joann's, I saw Kona muslin, different from Kona Cotton. The muslin was thicker than Roclon, but softer than the Kona Cotton. It was 7.99/yard.
I love muslin as my white. It is so soft and cuddly when washed. I use Warm &White batting which is denser and the backing colors don't show through.