I might as well chime in.
I've never owned or operated a ricer. I don't understand why it's called a "ricer." It looks like a bulky, inefficient, one-purpose appliance, to me. If more discussion can change my mind, I'm open to it...
I have a handheld masher. And if our industrial design student OP even cares at this point, I do not like it for the following reasons:
1. It stores in drawers poorly. The mashing end should swivel and lock, allowing it to be stored as a flat utensil.
2. The mashing end should be interchangeable - big, medium and fine mash - just like an expensive ricer with different sized sieves.
Either way, mashing is labor-intensive; any idea to relieve us of the work is welcome.