I was at a quilt show back in April and Hobbs had a booth. They had a sample of each type of batting - quilted up and washed. I couldn't tell the difference - they all looked the same because they were small samples LOL!!
I always intend to measure a quilt before and after washing to see the shrinkage, but always forget...sigh!! I do do a lot of handquilting, so i'm sure that minimizes the shrinkage.
btw - i'm a quilters dream cotton person...