We started that with our first Yorkie, Biff, and he took to it right away and we will definitely use it when we pick up our little girl in a few weeks. Thank goodness Biff's on the small side because I've heard the complaint that some boys lift their legs too high and it goes on the wall or floor. It is a little expensive, but honestly it's worth it for us since Biff would otherwise need to be taken out WAY too often. We still take him outside for walks and he will go outside, infact he prefers to poop outside. In a pinch he'll use the box with no complaints since he knows he gets treats when he goes in there
Sometimes he does take pieces out and play with them on the floor which makes a bit of a mess, but it's not a constant habit. Maybe a few times a month he'll do that. Great stuff though.