The phrase "This will still clean right down to the concrete even after the snow has been driven over multiple times" isn't mine. I have found with the rubber mat 'sandwiched' between the cutting edge and the blade proper cleans best on snow that has not been driven over. I know I am going to get some criticism for saying this, but that is why I most often push backwards (very carefully) and do not pull the blade through the snow. On my blacktop driveway I can get right to the pavement in powder snow or the wet/sticky variety we usually get here. Equally important to me, is the fact that I can move snow back onto the lawn without damaging the turf- whether frozen or not. I also routinely plow "roads" across my lawn from the woodshed to my deck to facilitate the delivery of firewood to the house. That is done by pulling the blade and with minimal damage to the turf.
Frank