I used poly on the roll for some lap quilts when I got back into quilting a couple of years ago. Maybe it was my lack of experience with machine quilting at the time, but I had problems with the sandwich shifting even though they were pin basted quite well. Switched over to Warm & Natural but have since switched to Hobb's Heirloom which is all cotton and non-scrim. Seems to be a little lighter weight and softer/more flexible than W&N. Haven't tried any wool or bamboo batting (yet). I'm sure you'll get pro's and con's for the myriad of choices but in the end it boils down to the feel and look of the finished quilt that you like, and it's intended use.