I'll add my penny to the jackpot on this one! I love wool batting: don't have a clue on how it works for machine quilting but I hand quilted a full size quilt and it was the easiest to needle of all the battings I've tried in 30 yrs of quilting. Being a natural fiber I think it "breathes" better: people who find a polyester batting makes the quilt too warm can tolerate wool just fine. Goes through the washer/dryer with no problem that I can see. I've got a queen -size wool batting sitting unopened in the corner of my very messy sewing room just waiting for me to finish this unending scrappy thing (sorry, there's no other way to describe this project!)