Are you planning on quilting it yourself? Are you doing the quilting by hand or machine? Some battings that are thicker are meant to by tied not quilted by machine so make sure you look at that when buying batting. Thick batting can be tricky to quilt on by machine and if long arming, you may actually have to make adjustments to the height of your foot. If you are going to send your top out to be quilted by someone else, I would discuss it with them, as they would know their machines and what battings work well.