I would recommend Cathay Pacific over SQ for the SIN-HKG route
as the food is generally better from what I saw from
airlinermeals.net. Moreover, one big plus for CX is not having to
put up with the "ang moh" elitism and robotic plastic smile that
plaques a fair proportion of SQ's cabin crew.
It's quite true that their seating arrangement is somewhat more
crammed than SQ, with frequent complains by dissastified pax about
broken seat backs etc. However, I'm confident that CX had taken
these feedback to task and improve on their products after losing
the Skytrax best airline 2006 award to fellow OneWorld member
British Airways.