What has been your experience with the Blanke Permat product? I know Blanke's Unimat was not so good and got pulled from the market. I can't find much on Permat. Has anyone used it? The tile guy I spoke to likes it better than Schulter's products and Nobleseal because it claims to improve the rigidity, so you don't need double ply where ditra would. We are putting 20" tile on a second floor, and I would like to use single sheet ply which permat says is okay.