I have a potato ricer, in fact my mother had a potato ricer so that is probably why I bought one long ago. I actually used mine a lot when making mashed potatoes for a large family. The blender would work, too. I've also used my big mixer to whip the potatoes.
But why I am responding to this thread is that I never thought of using it to make mashed cauliflower. I make cauliflower (fake potato) salad often. I guess I should dig out my potato ricer and see how it works with cauliflower.
We do keep learning, don't we? Hope you get a good answer to your OP question.