I use them because my feet change in size depending on fluid retention. Mine are purchased from Timpson's. I have tried some that claimed to be "memory foam" - more expensive and no better. It was years ago so no idea of brand.
I had an in sole made by the podiatry dept , which I used in my walking boot , but my everyday shoe I use Sketchers and personally I find I don’t need an insole in them as the memory foam in them is fine