Product review (5 stars): It definitely reduces vibrations to the floor
Expensive!  Are they worth it?  Well, I think so.

I've got my brand new top loading washer and front-loading dryer on the second floor.  I reluctantly bought these.  I needed something.  They do work.  For the price, yeah, I'd go for it.  If they were much higher, I'd find something else.  The pads really are jelly-like - at least the top half, so they do work, just use care when placing your appliance on them or else they'll rip apart.