For the vast majority of my quilts I use W&N. It's a combination of price, weight and looks. Most of my quilts are machine quilted either on my sewing machine or when I rent time on a long arm. The place that I rent time sells Hobbs batting and she says she can meet me on price (unless, I have one of those % off coupons on top of the sale price). The next time I need batting (I had just bought 10 or 12 yards when she told me this) I'll try it.
My very first quilt I was cautioned about the shrinkage and yes, I pre-shrunk my batting. Never again. I for one LOVE the shrinkage. It hides my quilting problems.
The weight of the quilt for me is good as well - except in a king size quilt -- then it's too heavy. Right now I'm hand quilting a king and I'm using Quilters' Dream for two reasons: the weight and more importantly so I can hand quilt. I did some hand quilting on a quilt for my nephew and thought there was no way I'd do it again. If I could have figured out how to machine quilt it I would have after only a couple of blocks.