Thought this was a gimmick that I fell for on instagram and you know what...they are kinda awesome. Has really helped improve my grip strength and has helped with my elbow rehab.
The risers some times don't want to stay together so if you clip the bottom during a step or something, could be an adventure but honestly, not an issue typically.
When you just HAVE to know exactly how much you are lifting. I do use this more often than I thought i ever would with a couple of my machines and loading dumbbells.