I was an instructor in the RAF when they decided to switch from using QFE as a landing datum to QNH overnight. I won't go into the numerous details of the arguement except that it was not very popular and was eventually changed back - except that now the radar circuit was flown on QNH, QFE being set by the pilot and setting confirmed by the controller on final approach.
Soon after, a mate was flying an instrument instructional sortie making an approach to a local airfield which was some 200' above our base and had cloud cover down to the deck. (Quite legal under the RAF rules at the time providing you planned to go around at DH). At about 300' on the Alt, my mate noticed the runway threshold just underneath the aircraft and made a hasty go around. He had not set QFE and the controller hadn't confirmed it.
In the subsequent incident report, he freely admitted that if he had done a check at the outer marker, the error would have been picked up.
So as well as finishing my coffee
I always check the height and make sure the GA alt is set in the alt window - as per the company SOPs.