I use both, and Love both! I tend to ( stock up) on Hobbs wool when Connecting Threads is having their batting sale & a couple times a year a sort of local quilt shop who carries all of the Dream battings has a sale & I grab the wools ( and the dream orient) at those sales.
Jan in VA - many longarm quilters use a wool batting along with a cotton when they want to really showcase their quilting. The wool batting's loft on top of the cotton really adds wonderful definition to the stitching. Fairly { common practice} in the longarm community among the quilters doing custom, show, & whole cloth quilting