Moderator, El Al and Marriott Bonvoy, FlyerTalk Evangelist
Join Date: Feb 2005
Location: SIN
Programs: SQ PPS, Mar LTT, Hyatt Glb, AA LTG, LY, HH, IC, BA, DL, UA SLV
Posts: 12,146
If you do make it upstairs you have a bunch of restaurants and some massage places upstairs.
If it doesn't work then you may want to go out through normal immigration so that you have more options with regards to restaurants and shops. With 5 hours you could hop the Airport Express train to the city, have a nice meal and a massage or catch a movie and then take the train back and meet them in the domestic lounge.