I've used black bat on several quilts with lots of black background and backing. Just don't want to risk bearding! I've used both Hobbs Tuscany and Hobbs Heirloom and recently have used the black poly from Keepsake Quilting (maybe Quilters Dream, but can't remember and their newest catalog doesn't have any bats)--actually on the quilt waiting for binding, I wanted to double the bat and used the black poly on top of a Hobbs Heirloom.
I've not had lots of problems with significant bearding, but recently saw a quilt that really had lots of white "pokies" on the black backing.