Only tried once so far and temperatures were in the 50 F range and it seemed effective.  Heat from above made it easy to make sure two or three people sitting beneath it would feel the direct heat.  The head appears to be adjustable to make sure the best coverage of radiant heat is accomplished depending on the outdoor seating.  The wheels on the base makes it easy to move around.  Two people can easily lift it to bring inside tool shed for storage during rainy/snowy weather.  Good instructions and easy to install, however there was some difficulty with the last installation step where apparently the inner stiff wire did not move enough to allow the switch to seat into the main shaft fully. After sending photographs of the not fully seated switch, customer service assured that it was safe to use.