It all depends on what you want to accomplish with the batting. Before quilt batting becomes batting it is some type of fiber. Polyester, cotton, wool, bamboo, ect. Batting companies also blend these fibers together, such as 50% cotton and 50% bamboo, or 80% cotton, and 20% polyester, ect. The two major methods of making these fibers into batting is (1) Needled or Needle punched (2) Bonded Needled batting is when the factory sends the fibers through a machine that has hundreds of barbed needles that go back and forth through the fibers weaving them together. You end up with a products that is about 1/10 of 1" thick. The standard is to have 4 oz. of fibers per sq. foot of batting. Almost all cotton, wool, and other natural fibers are made into batting using this method. It comes with or without a scrim (Warm and Natural has a scrim) Scrim is a thin mesh that the batting is needled around, it gives the batting more strength from tugs and pulls. But it can bother some machines and can be a little more difficult to hand quilt. Most hand quilter perfer without scrim. Most polyester batting is bonded batting. You might have heard the slogan "Bonded batting doesn't beard" Bonded batting is made usually in either of two methods. Resin bonded or Thermal bonded, as the name implies. Resin bonded batting has a glue sprayed on to the fibers and they stick together as the glue drys. Thermal bonded batting uses heat to melt some of the fibers (low melt fibers) to the point where they adhere or stick to the regular fibers. You now have no glue or resin in the batting. Most factories are moving from the older method (resin bonding) to the newer method (thermal bonding) Bonded batting has lots of air space and can be very thin like a 2 oz. batting You can almost see through this batting (loft about 0.20") up to 20 oz batting (loft about 1.50"). So if you want a very puffy product when you are finished you would want a high loft or extra high loft batting. Polyester batting is usually referred to as 2oz or 3 oz Low Loft, 4 oz Medium Loft, 6 oz to 8 oz High Loft and 10 oz extra high loft). Polyester batting usually comes on a roll that is 48" or 96" wide. The oz. weight is usually measured in how much fiber is put into each lenier yard of product (not sq. foot like needled batting). So a 3 oz 48" wide and a 6 oz 96" wide product would be the same batting the 96" wide product has twice as much fiber because it is twice as wide. Polyester cost about 1/2 of what cotton cost, wool cost about twice as much as cotton. Polyester is not a natural fiber (oil based) and does not "breath" like the natural fibers. Most all the great quilting artist use a cotton batting. Folks that are making quilts for everyday use, usually use a polyester batting. Cotton batting gets fuller after each washing. (This is as the fibers loosen up from the needle processing. Where polyester batting starts to get less puffy as the fibers break down. Hope this information helps a few folks understand batting a bet better. www.batt-mart.com has a large selection of batting. They have HOBBS, THE WARM COMPANY, QUITERS DREAM, AIRTEX, FAIRFIELD, PELLON, other no brand name products