They will stretch over my wife's shoes and possibly mine but I haven't tried them. The floor tiles are big ones. I would advise somebody looking for safety on icy paths not to rely on pound shop ones even if they are still sold but the ones in the original post look quite substantial.
They are, I am on my fifth winter with them One thing I would advise though. Take them off your shoes/boots at least once a week and wash them under the tap in warm water, it removes all the salt/grit.