Air China F is better than SQ J. Now, not necessarily the food or the beverage selection, but the seat, bed, amenities, PJs and everything else. The service on Chinese carries is also pretty darn good, although they have a limited soft product to work with. While the crew's English may be far from fluent, the 'service' element is without question.
Air China operates two configurations for their A330. The majority have full flats, but there is a small sub-fleet with angled flat beds. But the flight is only 2 hours. Those seats (both full flat and angled) lack privacy, but the trade-off is that there are no cubby holes or tubes or cut-outs for your legs and feet while sleeping. In terms of sleep comfort, they are hard to beat.
Yes SQ has great crew, better than average food, and a reasonable drink selection. But once your meal has finished you have another 10 hours of comfort and snoozing to think of. A proper F seat/suite in a small and quiet cabin with dedicated crew and toilets, and service that revolves around your schedule rather than the cabin as a whole, is what will count.
And you save 7 hours!
