Every since the kids saw me using salt and pepper mills (particularly the salt mills), they've been obsessed and now have their friend obsessed with grinding salt over whatever. Now, you would think that because the kids are older now, 11 and 15, they would be more gentle. And they are... the problem is that there is so much more traffic/eaters in our home now that they almost have to do commercial use. I'm willing to have two sets of salt and pepper mill grinders...I'd just like some recommendations as to not only the ceramic grinders themselves but also the outer "hulls" that contain the salt and pepper. Thoughts??