We used one with MIL three years ago, it was so easy and much less distressing for her.
Mum was a terminal cancer patient, and every time they moved her or bathed her they asked me to leave the room, so I had never seen them use the slider.
Mum wanted to be at home for the end, so a few days before we took her home, I asked the nurses if I could stay whilst they moved/ washed Mum, as I was going to have to do it when we got home, and I would rather be shown the best way to do it, both for me and for her.
They agreed with me and let me help them, It certainly made me feel a lot more confident when we got home. X