Itinerary: JFK-NRT(DL 3799) 1 hour 40 minute layover (C class)
NRT-SIN(NW19) 13 hour layover (C class)
SIN-DPS(SQ944) (Y class)

(1) Will DL interline my luggage through to DPS?
(2) Do I really want DL to interline through to DPS (or am I better off checking it to SIN in case DL manages to lose it)?
(3) Assuming that the luggage is checked through to DPS, will I be able to stay airside in SIN, and use the Transit Hotel?