From my own perspective, while it sounds like it could be useful, it also sounds like it could induce carpal tunnel syndrome. Since I'm already struggling with that, I'd pass. Those steel slabs look like they have a bit of heft to them - perhaps you'd be better off taping together a few short card stacks & working with those. If you include jokers and extras, you could make eight seven card stacks, equal in size to the slabs, but much lighter. I think I've also hear of other magicians trying these but preferring to use cards because of the difference in weight changing the way the slabs are handled compared to cards.