I just finished reading all of the replies you received. I made a shoulder warmer (kind of shaped like the Puritan collars) for my sister this past Thanksgiving and she told me that it make her feel so calm, safe, and cozy even when she did not warm it in the the microwave. She liked it so much that she requested 7 more for family and friends. Then she asked for more. I went on line and looked at the weighted quilt sites and feel like that might be why they were such a hit. Thanks for asking about this topic because I really did think there was something to what she said but just could not explain it. - Rice would be too heavy for your quilt, but the narrow channels (tubes) helped to hold the rice in place and keep it from all going to the bottom of the collar. Hope you are as calm and contented as my sister once you get yours.