Hard for my kids to push down and when they do it tends to push away from the piano. It works but there are probably better extenders available, they may just be a lot more expensive. Proceed with caution.
I bought this for some of my very small students. It works fine at the grand piano but did not fit over the pedals of my digital pianos in a way that allowed the pedals to operate. (But it looks much nicer than a step stool.) It has a very classy look to it, but is very heavy and awkward to transport. I would still buy it again, however, since I haven't been able to find anything like it for the price.