Efficiency. He located the tank, filled it, acknowledged our presence briefly on the deck above, told us he would leave the receipt on the door...all in a very friendly voice. I did get the feeling that with the corvid-19 quarantine in effect he was letting us know that we were not needed!
From the moment that I indicated that I needed a delivery on the website to the time that the delivery driver was hanging the receipt on my door was about 4 days. I couldn't ask for a more timely service.