Nothing to complain about here.  I put this pad on a king size mattress myself.  Fit is good.  I think the key is to unzip the pad all the way, lay it on your mattress the correct way, fit it around the edges, tuck the bottom under the mattress, go around to the other side of the mattress, lift and pull through and zip it up.  Worked like a charm for me 7-10 minutes.  Good thing too, had a liquid spill the next day, wiped it clean, sprayed it, let it air dry, made the bed up.