These stools are high which was what I was looking for since we started potty training when Ella was about 32 inches high. This was a perfect height to help support her getting onto the potty and then accessing the sink to wash her hands. The platform is average size but of course with the added height be careful if they need to turn around while on the stool. There is a small chance it could tip over with the height as well so I would recommend supervision if the child is small.
This stool is a little pricier but it’s very stable. There is rubber around the base of the stool as well as on the top to help slipping. We started using this when Ella was 39 inches which seemed to be a great height to access the toilet as well as the sink. At this age, she’s much more independent with going to the potty so this stool has been used quite a bit and there is piece of mind to know that it’s extra stable if she’s using it on her own.