Harriet Hargrave was involved in the testing and development of some of the Hobbs products and you can still see her name mentioned on them. And, she and her daughter Carrie have developed and written a great book resource for quilters. She has a two day class that it very well done and offers lots of information. One of the resources she made available was a stack of different batting pieces. All fibers and combinations were in the group. The instruction was to use a top and backing of a good quality muslin and make a sandwich with each batting piece. Then, use it to practice different techniques of quilting. I kind of divided my squares in sections and used different kinds of threads as well. I used a permanent pen to carefully catalog what I had done. I loved the project. I now can look through my samples and decide on a batting for my projects that gives the look I want. I keep a few batts around but, as I rule, I buy only a couple at a time for the project intended. I made a king size quilt for a son and daughter in law and used silk and it was great. I have also used wool. I also notice that some quilt makers who publish their quilts tell about combinations of batting they use for special effects. The question is: What end result are you looking for and how do you plan to get to that end point. There are so many wonderful variables in today's quilting world. I really like my 'private' catalogs of examples.