I can't sleep on night flights, so I'd take a day flight if pos. bUT if you reckon you'd get some sleep, the sleeper service is better because there's no meal service to interrupt your sleep. Crew often leave the lights out on sleeper services and half the cabin is lying down by the times the cookies come around!

Once when we had a heavy ground delay at JFK, they did the food run on the ground and then just a post-takeoff cocktail service.