I think it's probably fair to say that airline aptitude tests and RAF tests will be looking for different things in a 'suitable candidate'. While both will be looking for potential flying ability, the BA ones also feature a personality quiz, where they seem to be looking for a sociable nature (ie, the ability to get on with someone you've just spent 12 hours cooped up in a flight deck with) and an aversion to risk taking, not necessarily qualities required by fighter pilots. I've not taken any RAF tests, but I imagine that the RAF will be looking for a number of other qualities not necessary for flying airliners.