I just finished the installation of the "Spendide Ariston" stackables in our 2012 Landmark and have run a couple of test loads. I haven't taken them on the road yet, so I'm concerned about them moving around. It appears to me that there is plenty of potential for that. My installation procedure included the guidelines submitted by "JohnDar" (thank you very much, they were invaluable) which included the removal of the false floor in the closet and installing a 3/4" plywood floor deck and the drip pan. My concern is that the rocking motion of the unit may be problematic. Do any of you seasoned travelers with stackables have any advice? Thanks for any suggestions you may have.