Product review (4 stars): Works as advertised - so far.
Conditions: Samsung front-load washer, cement floor, basement.

Problem: During spin cycles the whole house would shake and it would sound as if a helicopter was hovering overhead.  The washer also walked from time to time.

Result: No more hovering helicopters, and in over 3 weeks of use, the washer hasn't moved.

I would recommend this product.