My favorite is Hobbs Heirloom 80/20. I also like all of the Quilter's Dream battings. I don't like Warm and Natural. It's hard flat, it has no resilience or loft and doesn't give your quilting any definition, and if you quilt it at all close about stiff as a board.
The thinnest Quilter's Dream is also thin and fairly flat but it's not stiff when quilted fairly close.